A comprehensive resource on pathogenic bacteria, viruses, fungi, and parasites — from culture media and staining to clinical laboratory diagnosis, and self-assessment with interactive MCQs.
How to identify Epidermophyton floccosum: khaki-green powdery colony, club-shaped (beaver-tail) macroconidia in clusters, and the key feature that it produces macroconidia only and no microconidia.
The in vitro hair perforation test for dermatophytes: principle, procedure, and how to read it. Which organisms are positive, and how it separates T. mentagrophytes from T. rubrum and M. canis from M. equinum.
Why can Strongyloides stercoralis persist for decades and then turn deadly? Complete life cycle, the autoinfection and hyperinfection mechanism, clinical features, treatment with ivermectin, and why a single stool examination often misses it.
Why does Trichuris trichiura cause rectal prolapse in children but no lung symptoms, unlike Ascaris and hookworm? Complete whipworm life cycle, pathogenesis, treatment, and the barrel-shaped bipolar-plug egg that identifies it.
Why does pinworm cause itching at night and why is the whole household treated at once? Complete Enterobius vermicularis life cycle, the perianal egg-laying and retroinfection that drive reinfection, clinical features, and treatment.
An overview of stool concentration techniques used to detect intestinal parasites: what concentration means, the sedimentation and flotation methods, how each works, and how to choose the right one for a given specimen.
Why does routine stool microscopy miss Cryptosporidium, and why is it so dangerous in HIV/AIDS? Complete Cryptosporidium parvum and hominis life cycle, the autoinfection mechanism, treatment, and the modified acid-fast diagnosis.
How fluoroquinolones work: inhibiting DNA gyrase and topoisomerase IV, members like ciprofloxacin, resistance by QRDR mutations, uses, and tendon warnings.
What a bacteriocin is, how it differs from an antibiotic and a bacterial toxin, why bacteria make them (bacterial antagonism), how they kill target cells, and why bacteriocins like nisin matter today.
How aminoglycosides work: 30S binding and mRNA misreading, why they are bactericidal, members like gentamicin and amikacin, resistance, and toxicity.
The human microbiome explained for health science students: what it is, how we study it with sequencing, how it drives disease, and the new microbiome-based therapies.
How syndromic multiplex PCR panels diagnose respiratory, GI, CNS, and bloodstream infections, what the results mean, and where they mislead. For health science students.
The Trichophyton species that matter in the lab: colony and microscopic appearance, pencil-shaped macroconidia, endothrix vs ectothrix hair invasion, and how to tell T. rubrum from T. mentagrophytes.
The tinea infections explained by site: tinea capitis, corporis, pedis, cruris, unguium, and more. Common organisms, clinical features, and how the site names work.
