Nursing(Degree) · First Year · NUR101
Anatomy and Physiology
Anatomy and Physiology is one of the most important foundation courses for nursing students in Zambia. This course helps you understand how the human body is structured and how it functions, from major organs to body systems such as the nervous, cardiovascular, respiratory, and digestive …
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Anatomy and Physiology is one of the most important foundation courses for nursing students in Zambia. This course helps you understand how the human body is structured and how it functions, from major organs to body systems such as the nervous, cardiovascular, respiratory, and digestive systems. A strong grasp of this subject is essential for exams set by nursing schools and regulatory bodies in Zambia. At 25schools, we simplify complex anatomy concepts using exam-focused questions, diagrams, and clear explanations designed for nursing exams. Whether you are preparing for tests, assignments, or final examinations, this course builds the clinical understanding every successful nurse needs. Start studying with 25schools today and gain the confidence to excel in anatomy and physiology exams.
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Tuberculous Arthritis
Tuberculous arthritis is chronic, indolent monoarthritis caused by Mycobacterium tuberculosis, representing a diagnostic challenge in TB-endemic Zambia. Pathophysiology: haematogenous seeding of synovium from pulmonary (50%) or extrapulmonary focus. Chronic granulomatous synovitis → caseous necrosis → cartilage destruction → bone erosion → pannus → joint fibrosis, ankylosis. Pott's disease: spinal TB (50% of musculoskeletal TB)—thoracovertebral, paravertebral abscess (cold), gibbus deformity, spinal cord compression. Clinical: CHRONIC, INSIDIOUS monoarthritis (90%)—knee, hip, wrist, ankle. Pain, swelling, stiffness, mild warmth. Constitutional symptoms (50%): fever, night sweats, weight loss. Pott's: back pain, spinal tenderness, kyphosis, paraplegia. Diagnosis: HIGH INDEX SUSPICION—chronic monoarthritis, TB contact/ history. Radiographs: Phemister triad—juxta-articular osteopenia, peripherally located bony erosions, gradual joint space loss (late). Pott's: vertebral destruction, disc space narrowing, paravertebral soft tissue mass, gibbus. CHEST X-RAY: active TB in 50%. TST/IGRA positive. SYNOVIAL FLUID: inflammatory (WBC 10,000-20,000, lymphocytes), AFB smear positive <20%, culture + 80%, PCR (Xpert MTB/RIF) rapid, sensitive. SYNOVIAL BIOPSY: granulomas (90%), AFB, culture, PCR—gold standard. Management: ANTI-TUBERCULOUS THERAPY (6-12 months). SURGICAL DEBRIDEMENT for large effusion, pannus, instability, abscess, neurologic compromise (Pott's). Prognosis: excellent with early treatment; delayed diagnosis → irreversible joint destruction, ankylosis. Zambian context: HIGH PREVALENCE. Consider TB in any chronic monoarthritis. Xpert MTB/RIF increasingly available. Synovial biopsy definitive. ATT accessible, free. Surgery limited capacity.
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Chikungunya Arthritis
Chikungunya virus (CHIKV) is an alphavirus transmitted by Aedes mosquitoes, causing epidemic acute febrile illness with severe, debilitating polyarthritis. Zambia faces periodic outbreaks; recognition essential. Pathophysiology: viral synovitis, macrophage infiltration, persistent viral antigen, IL-6, TNF, IFN-α, MCP-1. Chronic arthritis: immune-mediated, viral persistence? Clinical: INCUBATION 2-6 days. SUDDEN ONSET high fever, severe ARTHRALGIA (90-100%), symmetric polyarthritis (hands, wrists, ankles, feet), TENOSYNOVITIS, EDEMA. Rash (maculopapular), conjunctivitis, myalgia, headache. ACUTE: self-limited 7-10 days. CHRONIC (>3 months, 30-60%): persistent symmetric polyarthritis, morning stiffness, tenosynovitis—mimics RA (RF/ACPA negative). Relapsing-remitting course over months-years. Risk factors for chronicity: age >40, severe acute disease, female, pre-existing arthritis. Diagnosis: CLINICAL—epidemic setting, fever + severe polyarthralgia. LABORATORY: acute phase—CHIKV RT-PCR (day 1-7), IgM anti-CHIKV (day 5+), IgG (convalescent). NORMAL RF, ACPA, ESR/CRP variable. Radiographs: no erosions. Differential: dengue (myalgia > arthralgia, haemorrhage), malaria, RA, reactive arthritis. Management: ACUTE: REST, ANALGESICS (paracetamol), NSAIDs. AVOID aspirin, NSAIDs in suspected dengue. CHRONIC: NSAIDs, hydroxychloroquine, methotrexate (refractory, persistent). Corticosteroids: short-term, low-dose. NO specific antiviral. Prevention: vector control. Prognosis: most recover fully; 30-60% chronic arthritis, typically non-erosive, functional impairment. Zambian context: Aedes present, outbreak risk. CHIKV in differential of acute febrile polyarthritis. Chronic CHIKV arthritis misdiagnosed as RA (but RF/ACPA negative). Hydroxychloroquine, methotrexate accessible. Public health: surveillance, vector control.
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Rheumatic Fever and Post-Streptococcal Arthritis
Acute rheumatic fever (ARF) is autoimmune sequela of Group A Streptococcus pharyngitis, causing arthritis, carditis, chorea, and subcutaneous nodules. Post-streptococcal reactive arthritis (PSRA) is distinct entity. For Zambian students: ARF remains major cause of acquired heart disease; RHD burden high. Pathophysiology: molecular mimicry—M protein antibodies cross-react with cardiac myosin, sarcolemmal proteins, neuronal antigens, synovium. PSRA: less specific immune complex-mediated. Clinical: ARTHRITIS (70-75%)—MIGRATORY POLYARTHRITIS, large joints (knees, ankles, wrists, elbows), exquisitely painful, dramatic response to salicylates, NON-EROSIVE, NO chronic arthropathy. CARDITIS (50-60%)—pancarditis, valvulitis (mitral > aortic), regurgitation, heart failure, pericarditis; CHOREA (10-30%)—Sydenham, delayed; ERYTHEMA MARGINATUM (<10%)—pink macules, serpiginous, truncal; SUBCUTANEOUS NODULES (<5%)—extensor surfaces. PSRA: acute arthritis, less migratory, lacks other Jones criteria, prolonged course, less responsive to salicylates. Diagnosis: JONES CRITERIA (revised) for ARF: evidence of preceding GAS infection (throat culture, ASO titre, anti-DNase B) + 2 major OR 1 major + 2 minor (fever, arthralgia, elevated acute phase reactants, prolonged PR). PSRA: arthritis + GAS + NOT meeting Jones. Management: ARF—ANTIBIOTICS (benzathine penicillin G once, eradication). ARTHRITIS: ASPIRIN (high-dose, dramatic response) or NSAIDs. CARDITIS: corticosteroids if severe. CHOREA: supportive, haloperidol, valproate. SECONDARY PROPHYLAXIS: benzathine penicillin G q3-4 weekly (duration: no carditis → 5 years or 21y; carditis with residual → 10 years or 40y; severe valve disease → lifelong). PSRA: secondary prophylaxis controversial; consider 1 year. Prognosis: arthritis heals without sequelae. RHD: progressive, requires valve surgery. Zambian context: HIGH RHD BURDEN. ARF often underdiagnosed. ASO titre accessible. Benzathine penicillin cheap, widely available. Secondary prophylaxis adherence critical. RHD registers, nurse-led prophylaxis programs.
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Amyloidosis
Amyloidosis is a group of protein misfolding disorders characterized by extracellular deposition of insoluble, fibrillar amyloid protein in tissues and organs, leading to progressive organ dysfunction. For Zambian tertiary nursing and medical students, understanding amyloidosis is essential for differential diagnosis of cardiomyopathy, nephrotic syndrome, hepatomegaly, and autonomic neuropathy, as well as recognition of its association with chronic inflammatory conditions (rheumatoid arthritis, ankylosing spondylitis, TB, bronchiectasis) and multiple myeloma—all relevant to Zambian clinical practice. The pathophysiology of amyloidosis is unified by the conversion of normally soluble proteins into insoluble beta-pleated sheet fibrils that resist proteolysis, deposit in extracellular spaces, and progressively disrupt tissue architecture and function. Over 30 different proteins can form amyloid fibrils, classified by the precursor protein. The most common systemic forms are: AL (primary) amyloidosis—immunoglobulin light chains produced by clonal plasma cells (multiple myeloma, MGUS); AA (secondary) amyloidosis—serum amyloid A protein (SAA), an acute phase reactant synthesized by the liver in response to chronic inflammation (chronic infections—TB, bronchiectasis, osteomyelitis; inflammatory arthritis—RA, AS, JIA; periodic fever syndromes); ATTR amyloidosis—transthyretin (hereditary, senile systemic); and dialysis-related amyloidosis—β2-microglobulin (end-stage renal disease, long-term dialysis). The clinical presentation of amyloidosis is notoriously nonspecific and variable, depending on organ distribution and amyloid type. CONSTITUTIONAL: fatigue, weight loss, anorexia—almost universal. RENAL (50-70%): proteinuria (often nephrotic range, >3g/24h), progressive chronic kidney disease, renal vein thrombosis. Renal involvement is most common in AL and AA. CARDIAC (50% AL, >90% ATTR): restrictive cardiomyopathy—diastolic dysfunction, progressive heart failure with preserved ejection fraction, low-voltage ECG, concentric left ventricular hypertrophy on echocardiography with granular sparkling texture, elevated biomarkers (BNP, troponin). Cardiac amyloidosis carries the worst prognosis. NEUROLOGIC (15-20%): peripheral neuropathy (symmetrical, distal, sensorimotor; carpal tunnel syndrome is often early manifestation—50% of AL), autonomic neuropathy (orthostatic hypotension, gastroparesis, erectile dysfunction, urinary retention). GASTROINTESTINAL (20-30%): hepatomegaly (firm, nontender, elevated alkaline phosphatase out of proportion to transaminases), splenomegaly, macroglossia (10-20%, virtually pathognomonic for AL), malabsorption, gastrointestinal dysmotility. SOFT TISSUE: periorbital purpura (raccoon eyes—from vascular fragility, amyloid infiltration), subcutaneous nodules, arthropathy (shoulder pad sign—periarticular infiltration). Diagnosis of amyloidosis requires high index of suspicion and tissue biopsy. Screening: when amyloidosis is suspected, ABDOMINAL FAT PAD ASPIRATION is the least invasive, safest initial test (sensitivity 70-80% for systemic amyloidosis). Other easily accessible biopsy sites: minor salivary gland (lip biopsy), rectal mucosa, bone marrow (especially if AL suspected). Positive Congo red staining demonstrates apple-green birefringence under polarized light—the diagnostic gold standard. Once amyloid is detected, TYPING is essential to determine the specific precursor protein, as treatment is type-specific. Immunohistochemistry, immunofluorescence, or mass spectrometry-based proteomic analysis on fixed tissue distinguishes AL (kappa/lambda light chain restriction), AA (resistant to potassium permanganate pretreatment), ATTR, and other types. Serum and urine immunofixation electrophoresis and serum free light chain assay identify monoclonal light chains (AL). Acute phase reactants (ESR, CRP) and SAA levels are elevated in AA. Genetic testing for TTR mutations confirms hereditary ATTR. Echocardiography with strain imaging, cardiac MRI (late gadolinium enhancement, T1 mapping), and technetium pyrophosphate scintigraphy (highly sensitive/specific for ATTR cardiac amyloid) assess cardiac involvement. Management is type-specific and multidisciplinary. AL AMYLOIDOSIS: Treatment targets the underlying clonal plasma cell dyscrasia. Regimens adapted from multiple myeloma: bortezomib (proteasome inhibitor) + cyclophosphamide + dexamethasone (CyBorD); daratumumab (anti-CD38 monoclonal antibody) + CyBorD is new standard. Autologous stem cell transplantation in highly selected patients. Supportive care: diuretics for heart failure, fluid management for nephrotic syndrome. AA AMYLOIDOSIS: Definitive treatment is AGGRESSIVE CONTROL OF THE UNDERLYING CHRONIC INFLAMMATORY DISEASE. In Zambian context: treat tuberculosis, bronchiectasis, osteomyelitis with appropriate antimicrobials; optimize therapy for rheumatoid arthritis, ankylosing spondylitis (methotrexate, sulfasalazine). Anti-IL-1 (anakinra) and anti-IL-6 (tocilizumab) therapies are highly effective in refractory AA but unavailable in Zambia. ATTR AMYLOIDOSIS: Hereditary ATTR—liver transplantation (replaces variant TTR production with wild-type); tafamidis (TTR stabilizer) slows neurologic and cardiac progression; patisiran and inotersen (gene silencers) reduce TTR production. Senile systemic ATTR: tafamidis. SUPPORTIVE CARE is essential across all types: management of heart failure (cautious diuresis—amyloid hearts are preload-dependent, avoid beta-blockers, ACE inhibitors may precipitate hypotension), neuropathic pain (gabapentin, pregabalin), orthostatic hypotension (fludrocortisone, midodrine, compression stockings), nephrotic syndrome (salt restriction, diuretics, ACE inhibitors, anticoagulation for thromboembolic risk). Prognosis is highly variable by amyloid type, organ involvement, and treatment access. AL amyloidosis: untreated, median survival 6-12 months (cardiac involvement worst, <6 months). With modern therapy, median survival 3-5 years, even longer with cardiac response. AA amyloidosis: prognosis primarily determined by ability to control underlying inflammation; renal failure is major cause of morbidity/mortality. Zambian context: Amyloidosis is almost certainly underdiagnosed. The high burden of chronic infections (TB, bronchiectasis, chronic osteomyelitis) and inflammatory rheumatic diseases (RA, AS) predicts a significant, unrecognized burden of AA amyloidosis—a potentially preventable and treatable cause of progressive kidney disease and death. Renal biopsy services are limited; abdominal fat pad aspiration, minor salivary gland biopsy are feasible with basic pathology support. Congo red staining is inexpensive, widely available in tertiary hospital pathology departments. However, amyloid typing (immunohistochemistry, mass spectrometry) is largely unavailable in Zambia. Clinical-epidemiologic typing—AA amyloidosis in a patient with long-standing TB or RA, AL amyloidosis in a patient with monoclonal gammopathy, unexplained nephrotic syndrome, or macroglossia—is a pragmatic diagnostic approach. Treatment of AA amyloidosis is treatment of the underlying chronic infection or inflammation—entirely feasible with existing antimicrobials and immunosuppressants. Recognition of amyloidosis as a complication of uncontrolled chronic disease provides a powerful motivation for clinicians to optimize management of these conditions, not only for symptom control but for prevention of irreversible, fatal organ damage. This topic equips Zambian healthcare workers with the knowledge to suspect, diagnose, and type amyloidosis with available resources, implement disease-specific treatment, provide supportive care, and—most importantly—prevent AA amyloidosis through effective management of chronic infections and inflammatory diseases.
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Hereditary Hemochromatosis
Hereditary hemochromatosis (HH) is an autosomal recessive disorder of iron metabolism characterized by excessive dietary iron absorption and progressive iron deposition in parenchymal cells of liver, heart, pancreas, joints, pituitary, and skin, leading to multi-organ dysfunction. For Zambian tertiary nursing and medical students, understanding HH is essential for differential diagnosis of arthritis (particularly of the hands), cardiomyopathy, diabetes, and unexplained liver disease, and for recognizing that EARLY DIAGNOSIS AND TREATMENT (phlebotomy) PREVENTS COMPLICATIONS AND RESTORES NORMAL LIFE EXPECTANCY. The vast majority (80-90%) of HH is caused by homozygous mutation in the HFE gene (C282Y), with a minority of cases due to other HFE mutations (H63D, S65C) or non-HFE mutations (hemojuvelin, hepcidin, transferrin receptor 2, ferroportin). The pathophysiologic consequence is INADEQUATE PRODUCTION OF HEPCIDIN—the master regulator of iron homeostasis. Hepcidin, synthesized by hepatocytes, binds to ferroportin (the sole cellular iron exporter) on enterocytes and macrophages, inducing its internalization and degradation, thereby blocking iron export into plasma. In HH, hepcidin deficiency causes UNOPPOSED FERROPORTIN ACTIVITY → unregulated intestinal iron absorption (2-4mg/day instead of 1-2mg) and inappropriate release of iron from macrophages → progressive accumulation of iron in parenchymal cells. Total body iron increases from 3-4g (normal) to 20-40g over decades. Iron catalyzes Fenton reaction → hydroxyl radical generation → lipid peroxidation, mitochondrial dysfunction, DNA damage, stellate cell activation → fibrosis, cirrhosis, organ failure. Importantly, iron loading is GRADUAL; clinical manifestations typically appear in men >40 years and postmenopausal women (menstruation, pregnancy provide physiologic phlebotomy). The clinical presentation of HH is insidious, with non-specific symptoms often attributed to aging or other diseases. EARLY SYMPTOMS (often overlooked): fatigue, lethargy, arthralgia, weight loss, abdominal pain. LIVER DISEASE (70-80%): hepatomegaly (firm, nontender), elevated transaminases (mild), cirrhosis (20-30% of untreated), hepatocellular carcinoma (200-fold increased risk in cirrhotic HH, leading cause of death). ARTHROPATHY (40-70%): characteristic osteoarthritis-like arthropathy of SECOND AND THIRD METACARPOPHALANGEAL JOINTS (MCP 2,3—hook-like osteophytes on radiograph), also wrists, hips, knees, ankles. Arthropathy is CHRONIC, PROGRESSIVE, and DOES NOT IMPROVE WITH IRON DEPLETION—the most disabling long-term sequelae for many patients. CARDIAC (15-30%): dilated cardiomyopathy (heart failure), arrhythmias, restrictive physiology. ENDOCRINE (40-60%): DIABETES MELLITUS ('bronze diabetes', 30-60%, due to pancreatic iron deposition and insulin resistance), hypogonadism (pituitary iron deposition → decreased libido, impotence, amenorrhea, osteoporosis), hypothyroidism, hypoparathyroidism. SKIN: hyperpigmentation ('bronze diabetes', melanin and iron deposition, slate-gray discoloration, generalized, sun-exposed areas). Diagnosis requires HIGH INDEX OF SUSPICION—HH is the MOST COMMON GENETIC DISORDER IN EUROPEAN POPULATIONS (C282Y homozygosity 1:200-1:400), but also occurs in African populations with distinct mutations (ferroportin disease, African iron overload). SCREENING: Transferrin saturation (TSAT) >45% is the earliest, most sensitive biochemical abnormality; elevated fasting TSAT >45% (men) or >40% (women) warrants further investigation. Serum ferritin: elevated (>300 ng/mL men, >200 ng/mL women), reflects body iron stores; however, ferritin is also an acute phase reactant—elevated in inflammation, infection, liver disease, malignancy. If TSAT >45% AND ferritin elevated, proceed with GENETIC TESTING for HFE mutations (C282Y, H63D). C282Y homozygosity or compound heterozygosity (C282Y/H63D) with elevated iron indices confirms diagnosis. LIVER BIOPSY is no longer required for diagnosis in most patients with typical genetic and biochemical profile, but is indicated for: ferritin >1000 ng/mL (high risk of cirrhosis), elevated transaminases, hepatomegaly, or suspected coexistent liver disease (alcohol, viral hepatitis, NAFLD). Biopsy assesses fibrosis/cirrhosis and quantifies hepatic iron index (≥1.9). MRI (T2*, R2* relaxometry) non-invasively quantifies liver and cardiac iron. Arthropathy: radiographs of hands—MCP 2,3 joint space narrowing, subchondral cysts, hook-like osteophytes (pathognomonic). Management: PHLEBOTOMY (VENESECTION) is the cornerstone of therapy—simple, safe, inexpensive, and life-saving. INDUCTION PHASE: remove 450-500 mL whole blood (200-250 mg iron) weekly until ferritin 50-100 ng/mL and TSAT <50%. Typically 1-3 years (25-40 phlebotomies). MAINTENANCE PHASE: phlebotomy q1-4 months to maintain ferritin 50-100 ng/mL, TSAT <50%, lifelong. MONITOR: ferritin, TSAT, hemoglobin q3 months. IRON CHELATION (deferoxamine, deferasirox, deferiprone) reserved for patients with anemia, severe cardiac disease, or poor venous access. MANAGEMENT OF COMPLICATIONS: Arthropathy: NSAIDs, analgesics, joint replacement. Diabetes: oral agents, insulin. Hypogonadism: testosterone replacement. Cirrhosis: hepatocellular carcinoma surveillance (ultrasound q6 months). Heart failure: standard therapy. DIETARY COUNSELING: AVOID iron supplements, vitamin C supplements (enhances iron absorption), multivitamins with iron; AVOID raw shellfish (Vibrio vulnificus risk in iron-loaded patients); limit alcohol (hepatotoxic, increases iron absorption); no need to restrict dietary iron (heme/non-heme) except in massive overload. FAMILY SCREENING: CASCADE TESTING—all first-degree relatives of affected patients should undergo HFE genotyping and iron studies. Asymptomatic C282Y homozygotes with normal iron indices: monitor TSAT/ferritin annually; initiate phlebotomy when ferritin elevated. Prognosis: With EARLY DIAGNOSIS AND PHLEBOTOMY INITIATED BEFORE CIRRHOSIS DEVELOPS, patients have NORMAL LIFE EXPECTANCY. If cirrhosis is present at diagnosis, life expectancy is reduced due to hepatocellular carcinoma risk, which persists despite iron depletion. Arthropathy does not improve with phlebotomy. For Zambian clinicians, hereditary hemochromatosis presents a different epidemiology than in European populations. HFE mutations are less common in indigenous African populations, though occur in African-Europeans. However, an important differential diagnosis is AFRICAN IRON OVERLOAD (Bantu siderosis)—a condition described in sub-Saharan Africa associated with consumption of traditional beer brewed in iron drums/pots, leading to extremely high dietary iron intake and progressive iron overload with portal fibrosis, but less parenchymal deposition and lower cirrhosis/HCC risk than HH. This condition is decreasing with urbanization but still encountered. Additionally, TRANSFUSIONAL IRON OVERLOAD (thalassemia, sickle cell disease) is common in Zambia. The diagnostic approach to suspected iron overload in Zambia must consider all these etiologies. Genetic testing for HFE mutations may be unavailable or negative; in such cases, a diagnosis of non-HFE iron overload (ferroportin disease, African iron overload, transfusional) is made clinically, with emphasis on EXCLUSION OF SECONDARY CAUSES OF IRON OVERLOAD (transfusions, excess oral iron, chronic liver disease, dysmetabolic iron overload syndrome). Liver biopsy with hepatic iron quantification (if available) distinguishes parenchymal (HH, African iron overload) from reticuloendothelial (transfusional, ferroportin disease) iron loading. PHLEBOTOMY IS EFFECTIVE AND INDICATED FOR ALL CAUSES OF IRON OVERLOAD WITH PROGRESSIVE IRON ACCUMULATION AND END-ORGAN DAMAGE. It is safe, inexpensive, and can be implemented in district hospitals. Patient education regarding the rationale for phlebotomy, the lifelong nature of maintenance therapy, and the importance of family screening is essential. This topic equips Zambian healthcare workers with the knowledge to recognize iron overload syndromes, distinguish hereditary from acquired causes with available resources, initiate life-saving phlebotomy therapy, and prevent the irreversible complications of cirrhosis, cardiomyopathy, diabetes, and crippling arthropathy.
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Topic 168Coming soon
Wilson's Disease
Wilson's disease (WD) is an autosomal recessive disorder of copper metabolism caused by mutations in the ATP7B gene, leading to pathological copper accumulation in the liver, brain, cornea, and other organs. For Zambian tertiary nursing and medical students, understanding WD is essential for differential diagnosis of liver disease (particularly in children and young adults), movement disorders, neuropsychiatric symptoms, and for recognizing that this is a RARE BUT TREATABLE CAUSE OF CIRRHOSIS AND NEUROLOGIC DISABILITY—EARLY DIAGNOSIS AND LIFE-LONG CHELATION THERAPY PREVENT DISEASE PROGRESSION AND RESTORE NORMAL FUNCTION. The ATP7B gene encodes a copper-transporting P-type ATPase expressed primarily in hepatocytes, responsible for incorporating copper into apoceruloplasmin (to form functional ceruloplasmin) and EXCRETING EXCESS COPPER INTO BILE. Loss-of-function mutations → impaired biliary copper excretion → progressive hepatic copper accumulation → hepatocyte injury, steatosis, inflammation, fibrosis, cirrhosis. When hepatocyte copper storage capacity is exceeded, copper is released into the circulation and deposited in extrahepatic tissues: BRAIN (basal ganglia—putamen, globus pallidus, caudate; brainstem, cerebellum), CORNEA (Descemet's membrane—Kayser-Fleischer rings), KIDNEYS (renal tubular dysfunction), and other organs. The clinical presentation of WD is extraordinarily diverse, with hepatic and neuropsychiatric manifestations predominating. HEPATIC PRESENTATION (40-60%): May mimic virtually any liver disease. Asymptomatic hepatomegaly, isolated elevated transaminases. Acute hepatitis (often misdiagnosed as viral). ACUTE LIVER FAILURE (5-10%)—severe Coombs-negative hemolytic anemia (copper-induced oxidative damage to RBC membranes), acute renal failure, coagulopathy, rapidly progressive jaundice; typically in adolescents/young adults, frequently fatal without urgent liver transplantation. Chronic liver disease—cirrhosis (micronodular), portal hypertension, ascites, variceal hemorrhage, synthetic dysfunction. NEUROLOGIC PRESENTATION (40-60%): Typically presents in second-third decade, often years after hepatic involvement. MOVEMENT DISORDER is the cardinal feature—DYSARTHRIA (slurred speech, scanning speech), DYSPHAGIA, DROOLING, DYSTONIA (fixed postures, limb contractures), TREMOR (wing-beating tremor—proximal, coarse, present with arms abducted, elbows flexed—highly characteristic), ATAXIA, CHOREA, ATHETOSIS, PARKINSONISM (bradykinesia, rigidity). NEUROPSYCHIATRIC PRESENTATION (30-50%): Depression, anxiety, personality changes, irritability, cognitive decline, psychosis. Psychiatric symptoms frequently precede neurologic manifestations and lead to misdiagnosis. OPHTHALMIC: KAYSER-FLEISCHER RINGS are the pathognomonic sign of WD—golden-brown, greenish, or reddish-brown granular pigment deposits in Descemet's membrane of the cornea, visible by slit-lamp examination (100% of patients with neurologic WD, 50% of those with hepatic WD). SUNFLOWER CATARACTS (anterior subcapsular, rarely impairs vision). OTHER ORGAN INVOLVEMENT: Renal (proximal renal tubular acidosis, Fanconi syndrome—aminoaciduria, glycosuria, phosphaturia, hypercalciuria → nephrolithiasis), Skeletal (premature osteoporosis, osteoarthritis, arthropathy), Cardiac (cardiomyopathy, arrhythmias), Endocrine (hypoparathyroidism, infertility, recurrent miscarriage). Diagnosis requires HIGH INDEX OF SUSPICION—WD is rare (1:30,000) but treatable, and delayed diagnosis causes irreversible neurologic disability or fatal liver failure. Diagnostic scoring system (Leipzig) integrates clinical, biochemical, and genetic findings. SCREENING TESTS: SERUM CERULOPLASMIN (low <20 mg/dL, sensitivity 80-90%—normal in inflammation, pregnancy, estrogen therapy). 24-HOUR URINARY COPPER EXCRETION (>100 mcg/24h, sensitivity 80-90% in symptomatic WD). SERUM FREE COPPER (non-ceruloplasmin-bound copper) elevated (>25 mcg/dL). KEY DIAGNOSTIC PITFALL: In patients with acute liver failure, urinary copper may be extremely high, and serum ceruloplasmin may be low due to synthetic dysfunction, but these findings are not specific; a high index of suspicion is required. OPHTHALMOLOGY: Slit-lamp examination for Kayser-Fleischer rings. LIVER BIOPSY: Hepatic copper quantification (>250 mcg/g dry weight, gold standard). However, liver biopsy is invasive and may be contraindicated in coagulopathy. GENETIC TESTING: ATP7B mutation analysis—definitive; two pathogenic mutations confirm diagnosis. In Zambia, genetic testing is largely unavailable; diagnosis rests on clinical, biochemical, and ophthalmologic findings. IMAGING: Brain MRI is the single most useful neuroimaging study in suspected neurologic WD. Characteristic findings: T2-weighted hyperintensity in BASAL GANGLIA (putamen, globus pallidus, caudate), thalamus, brainstem, cerebellum; 'face of the giant panda' sign (midbrain) and 'face of the miniature panda' sign (pons) are highly characteristic. CT may show hypodensities, atrophy, but less sensitive. Management is LIFELONG and DIVIDED INTO THREE PHASES: INITIAL TREATMENT (decoppering), MAINTENANCE THERAPY, and LIVER TRANSPLANTATION (for decompensated cirrhosis, acute liver failure). INITIAL THERAPY (symptomatic patients): CHELATING AGENTS—bind copper, promote urinary excretion. D-PENICILLAMINE: first-line, 750-1500 mg/day in divided doses, with pyridoxine 25-50 mg/day (antagonizes pyridoxine). Adverse effects: early (hypersensitivity—fever, rash, lymphadenopathy, 20-30%—manage with drug holiday, corticosteroids, rechallenge) and late (nephrotoxicity, bone marrow suppression, Goodpasture syndrome, myasthenia gravis, elastosis perforans serpiginosa). TRIENTINE: alternative chelator, fewer adverse effects, 900-2700 mg/day. ZINC ACETATE: induces intestinal metallothionein, blocks copper absorption; preferred for MAINTENANCE therapy or asymptomatic patients. Slower onset, NOT for initial therapy in severe disease. MAINTENANCE THERAPY: after symptoms improve and 24h urinary copper stabilizes (usually 2-6 months), transition to MAINTENANCE dosing: D-penicillamine 750 mg/day, trientine 900 mg/day, OR zinc acetate 150 mg/day. Continue LIFELONG. MONITORING: 24h urinary copper (chelation: goal 200-500 mcg/24h; zinc: goal <75 mcg/24h), serum free copper (goal <15 mcg/dL), neurologic examination, liver biochemistries. NON-ADHERENCE IS FATAL—rapid, irreversible hepatic and neurologic decompensation. DIETARY COUNSELING: AVOID high-copper foods (shellfish, liver, nuts, chocolate, mushrooms, dried fruit) during initial therapy; less restrictive in maintenance. PROGNOSIS: With EARLY DIAGNOSIS AND ADHERENT LIFELONG THERAPY, hepatic disease stabilizes, neurologic symptoms improve in 50-80% (over 6-24 months), and life expectancy is NORMAL. Without treatment, progressive liver failure, severe neurologic disability, and death by age 30-40 are inevitable. LIVER TRANSPLANTATION: INDICATED for acute liver failure (fulminant WD) and decompensated cirrhosis unresponsive to medical therapy. TRANSPLANT IS CURATIVE for the hepatic phenotype (corrects ATP7B deficiency, normal copper metabolism), but neurologic improvement is variable and not guaranteed. For Zambian clinicians, Wilson's disease presents a diagnostic challenge. It is rare, but almost certainly underdiagnosed. The absence of genetic testing, limited access to slit-lamp examination (outside major cities), and lack of available copper quantification (serum free copper, 24h urinary copper, hepatic copper) restrict diagnostic confirmation. However, a CLINICAL DIAGNOSIS IS POSSIBLE in the majority of cases based on: 1) compatible clinical syndrome (unexplained liver disease in child/young adult; movement disorder with dysarthria, dystonia, tremor; neuropsychiatric deterioration), 2) Kayser-Fleischer rings by torch-light or direct ophthalmoscopy (visible in advanced cases), 3) low serum ceruloplasmin (available at University Teaching Hospital, Lusaka), and 4) exclusion of other causes. Brain MRI is increasingly available at tertiary centres. D-PENICILLAMINE and pyridoxine are available, inexpensive, and life-saving. Treatment should be initiated promptly upon strong clinical suspicion; diagnostic confirmation (including genetic testing) can be pursued later. Patient education regarding ADHERENCE is critical: 'one pill, twice a day, for the rest of your life—stopping can kill you'. Family screening: all first-degree siblings should be screened with ceruloplasmin, 24h urinary copper, and slit-lamp examination; genetic testing if available. This topic equips Zambian healthcare workers with the knowledge to recognize this rare but devastating and eminently treatable disease, initiate life-saving chelation therapy with available medications, and prevent the irreversible neurologic and hepatic consequences of delayed diagnosis.
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Topic 169Coming soon
Ochronosis (Alkaptonuria)
Alkaptonuria is a rare autosomal recessive disorder of tyrosine metabolism caused by deficiency of homogentisate 1,2-dioxygenase (HGD), leading to accumulation of homogentisic acid (HGA) and its oxidized polymer, which binds to collagen in connective tissues—ochronosis—causing progressive arthritis, cardiac valve disease, and renal stones. For Zambian students, recognition is essential as early diagnosis prevents disabling arthropathy. Pathophysiology: HGD gene mutations → HGA accumulates → oxidized to benzoquinone acetic acid → polymer binds irreversibly to collagen in cartilage, tendons, ligaments, skin, sclera, heart valves → tissue pigmentation (ochronosis) + collagen cross-linking → cartilage brittleness, fissuring, degeneration → premature, severe osteoarthritis. Clinical: HOMOGENTISIC ACIDURIA—urine turns DARK BROWN/BLACK on standing or alkalinization (diagnostic clue, often noticed in infancy—diapers stain black). OCULAR—BLUE-BLACK or GRAY PIGMENTATION of sclera (Osler's sign), pinna (cartilage, concha, antihelix), tympanic membrane. AURICULAR—cartilage thickened, irregular, slate-blue discoloration. CUTANEOUS—bluish-black pigmentation over nose, ears, axillae, groin, hands (sweat gland cerumen). ARTHROPATHY—progressive, premature, severe osteoarthritis affecting LARGE joints (knees, hips, shoulders) and SPINE (lumbar > thoracic). Onset 30-50 years. Characteristic: OCHRONOTIC SPONDYLOPATHY—narrowed disc spaces, dense calcification of intervertebral discs (massive, dense calcification on radiograph—PATHOGNOMONIC), osteoporosis, vertebral fusion, kyphosis. Tendon rupture (patellar, Achilles). CARDIAC—aortic stenosis (aortic valve pigmentation, fibrosis, calcification), mitral regurgitation, coronary artery calcification. RENAL—prostatic, renal calculi (HGA stones, radiolucent). Diagnosis: CLINICAL—dark urine, ochronotic pigmentation, early-onset severe osteoarthritis, pathognomonic radiographic disc calcification. URINE HGA—gas chromatography/mass spectrometry (qualitative, quantitative). HGA >4g/24h. GENETIC TESTING—HGD gene mutations. Radiographs: spine—dense, wafer-thin calcification of multiple intervertebral discs (lumbar), osteopenia, vertebral fusion; large joints—joint space narrowing, subchondral sclerosis, osteophytes (similar to OA). Management: NO CURE. NITISINONE—inhibits HPPD, upstream enzyme, reduces HGA production (effective, but cost, availability). High-dose vitamin C (antioxidant, may reduce polymer formation, controversial). ARTHROPATHY—NSAIDs, analgesics, physiotherapy, joint replacement (knee, hip—often required at younger age, technically challenging due to tissue pigmentation, stiffness). CARDIAC—echocardiogram surveillance, valve replacement. RENAL—hydration, stone management. Prognosis: normal lifespan; progressive arthropathy leading cause of disability. Zambian context: extremely rare; consider in unexplained early-onset severe OA, dark urine, ochronotic pigmentation. Radiographic spinal calcification diagnostic. No nitisinone; symptomatic management, joint replacement.
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Topic 170Coming soon
Relapsing Polychondritis
Relapsing polychondritis (RP) is a rare, immune-mediated inflammatory disorder characterized by episodic, progressive inflammation and destruction of cartilaginous structures (ears, nose, larynx, tracheobronchial tree) and proteoglycan-rich tissues (eyes, heart, blood vessels). For Zambian students, recognition is critical—RP is a diagnostic challenge, frequently missed, and carries life-threatening airway and cardiovascular complications. Pathophysiology: autoimmune targeting of type II collagen and matrilin-1; T-cell and humoral response; neutrophil, CD4+ T-cell infiltration at perichondrium → cartilage degradation, replacement by fibrous tissue, loss of structural integrity. Clinical: AURICULAR (90%)—acute, painful, erythematous, violaceous swelling of PINNA (sparing lobule—no cartilage). Recurrent episodes → floppy, cauliflower ear, hearing loss (external auditory canal collapse, serous otitis media), vestibular dysfunction. NASAL (60%)—acute nasal pain, erythema, swelling → saddle-nose deformity (loss of nasal bridge, 3-6 months). LARYNGOTRACHEOBRONCHIAL (50%)—hoarseness, aphonia, cough, dyspnea, stridor; subglottic stenosis, tracheal/bronchial collapse (life-threatening airway emergency). ARTHRITIS (70%)—acute, asymmetric, oligo/polyarthritis, large/small joints, non-erosive, migratory, spares axial. OCULAR (50%)—episcleritis, scleritis (anterior necrotizing, sight-threatening), uveitis, proptosis. CARDIOVASCULAR (20-30%)—aortic regurgitation (aortitis, aortic root dilation, annuloaortic ectasia), mitral regurgitation, thoracic/abdominal aortic aneurysm, vasculitis (large, medium vessels). CUTANEOUS (30%)—oral/genital aphthosis, nodules, purpura. RENAL (10%)—IgA nephropathy, mesangioproliferative GN. Neurologic (5%)—cranial neuropathies, aseptic meningitis. Diagnosis: CLINICAL—McAdam criteria (3+ of: bilateral auricular, nasal, laryngotracheal, non-erosive seronegative arthritis, ocular inflammation, audiovestibular) OR 1+ with biopsy confirmation. LABORATORY: no diagnostic test; elevated ESR/CRP (active disease); anemia, leukocytosis; RF/ACPA negative; ANA, anti-neutrophil cytoplasmic antibodies variable; anti-type II collagen antibodies (research). BIOPSY: auricular, nasal cartilage—perichondrial inflammation, chondrocyte degeneration, cartilage erosion, fibrosis. IMAGING: chest CT (tracheal wall thickening, calcification, luminal stenosis; expiratory CT—dynamic airway collapse); echocardiogram (aortic root, valve disease); CT/MR angiography (aneurysm, vasculitis). PFTs: flow-volume loop (fixed or variable extra-thoracic obstruction). Management: NO CURE. CORTICOSTEROIDS—mainstay; prednisone 0.5-1 mg/kg/day for acute flares, taper. MILD DISEASE (auricular, nasal, arthritis without airway): NSAIDs, dapsone, colchicine. MODERATE-SEVERE, REFRACTORY, ORGAN/LIFE-THREATENING (laryngotracheal, scleritis, aortitis, vasculitis): steroid-sparing immunosuppressants—methotrexate, azathioprine, cyclosporine, mycophenolate, cyclophosphamide. BIOLOGICS—TNF inhibitors (infliximab, adalimumab), tocilizumab (IL-6 inhibitor), rituximab (refractory). AIRWAY MANAGEMENT: endoscopic dilation, tracheostomy, stent, laryngotracheal reconstruction. CARDIOVASCULAR: aortic root/valve replacement, aneurysm repair (optimal timing challenging—active inflammation). Prognosis: chronic, relapsing-remitting; 5-year survival 90% (modern therapy); death—airway collapse, pneumonia, aortic aneurysm rupture, vasculitis, infection (immunosuppression). Zambian context: extremely rare; diagnostic challenge. Consider in recurrent auricular chondritis (sparing lobule), saddle-nose deformity, unexplained airway stenosis, aortic regurgitation in young. Biopsy accessible. Corticosteroids, methotrexate, azathioprine accessible. TNF inhibitors unavailable. High index suspicion.
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Topic 171Coming soon
Adult-Onset Still's Disease
Adult-onset Still's disease (AOSD) is a rare systemic inflammatory disorder of unknown etiology, considered the adult counterpart of systemic juvenile idiopathic arthritis (sJIA). It is a classic MAS (macrophage activation syndrome) mimic and a diagnosis of exclusion. For Zambian students, recognition is critical—AOSD presents with high fever, rash, arthritis, and marked systemic inflammation; prompt diagnosis prevents unnecessary investigations and enables life-saving therapy. Pathophysiology: autoinflammatory—IL-1, IL-6, IL-18, IFN-γ mediated; NLRP3 inflammasome activation; neutrophil, macrophage activation; no autoantibodies. Clinical: QUOTIDIAN FEVER (90-100%)—high (≥39°C), spikes once or twice daily, typically EVENING, returns to baseline, rigors; precedes other symptoms by weeks. EVANESCENT SALMON-PINK MACULOPAPULAR RASH (70-90%)—non-pruritic, trunk, extremities, appears with fever, Koebner phenomenon. ARTHRITIS (70-100%)—polyarthralgia, symmetric or asymmetric synovitis, wrists, knees, MCP, PIP, ankles; DESTRUCTIVE ARTHRITIS in chronic course (carpal ankylosis—PATHOGNOMONIC). SORE THROAT (70%)—prominent, early, pharyngitis (sterile). LYMPHADENOPATHY (50-70%)—tender, cervical. HEPATOSPLENOMEGALY (30-40%). SEROSITIS (30-40%)—pleuritis, pericarditis. MYALGIA. COMPLICATION: MACROPHAGE ACTIVATION SYNDROME (10-15%)—life-threatening cytokine storm: persistent fever, hepatosplenomegaly, cytopenias, hyperferritinemia, hypertriglyceridemia, hypofibrinogenemia, hemophagocytosis. Laboratory: LEUKOCYTOSIS (≥15,000, neutrophilia)—90%. THROMBOCYTOSIS. ELEVATED ESR, CRP. HYPERFERRITINEMIA (characteristic, often >5x normal, >10,000 ng/mL)—due to macrophage activation, cytokine-driven synthesis. GLYCOSYLATED FERRITIN (low, <20%)—more specific. Transaminitis. Negative ANA, RF. Diagnosis: YAMAGUCHI CRITERIA (sensitivity 93%)—MAJOR: fever ≥39°C ≥1 week, arthralgia/arthritis ≥2 weeks, typical rash, leukocytosis ≥10,000 (≥80% neutrophils). MINOR: sore throat, lymphadenopathy, hepatosplenomegaly, abnormal LFTs, negative RF/ANA. EXCLUSION: infection, malignancy, other rheumatic disease. 5 criteria (≥2 major) + exclusion. Fautrel criteria: includes ferritin, glycosylated ferritin. DIFFERENTIAL: sepsis, TB, malaria, EBV, HIV, lymphoma, SLE, RA, vasculitis. Management: NSAIDs—first-line for mild disease (indomethacin). CORTICOSTEROIDS—prednisone 0.5-1 mg/kg/day for moderate-severe, rapid response. STEROID-SPARING—methotrexate (chronic arthritis). BIOLOGICS—IL-1 inhibitors (anakinra, canakinumab)—highly effective, rapid, corticosteroid-sparing. IL-6 inhibitor (tocilizumab). MACROPHAGE ACTIVATION SYNDROME—IV pulse methylprednisolone, cyclosporine, anakinra, IVIG. Prognosis: three patterns—monocyclic (self-limited, 30%), polycyclic (relapsing-remitting, 30%), chronic articular (progressive destructive arthritis, 40%). MAS is life-threatening (mortality 10-20%). Zambian context: DIAGNOSIS OF EXCLUSION; must exclude infection (TB, malaria, EBV, HIV), lymphoma. Ferritin widely available; markedly elevated ferritin + quotidian fever + rash + arthritis = AOSD until proven otherwise. Glycosylated ferritin unavailable. NSAIDs, prednisone, methotrexate accessible. Anakinra, tocilizumab unavailable. MAS management challenging (cyclosporine available). High index suspicion.