Koilocytosis—characterized by squamous cells with enlarged, hyperchromatic nuclei surrounded by a clear perinuclear halo (halo effect)—is most commonly associated with human papillomavirus (HPV) infection. In urine cytology, these changes typically arise from squamous epithelium of the distal urethra, external genitalia, or areas of squamous metaplasia in the bladder. The nuclei appear wrinkled or raisin-like with irregular nuclear membranes, while the cytoplasm shows a distinct clear zone around the nucleus. Koilocytotic atypia is a hallmark of low-risk HPV strains (e.g., types 6 and 11) causing condylomas or high-risk strains (e.g., types 16 and 18) associated with squamous cell carcinoma. Distinguishing koilocytes from benign squamous cells or treatment effects is important for diagnosing HPV-related lesions.

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Zambia

• Naomi Miselo – 31 pts

• Visual Pathway Lesions
• Positive and Negative Symptoms
• Hallucinations and Delusions
• Antipsychotic Medications
• Emergency: Environmental Emergencies