Case Study 2025 BIO 215 WCSU

Aspergillus flavus

Mold exposure (grain, compost), liver failure, aflatoxin risk, immunocompromised patients, respiratory symptoms.

Candida albicans

White plaques in mouth (thrush), vaginal itching/yeast infection, immunosuppression, post-antibiotics.

Cryptococcus neoformans

Pigeon droppings, severe headache, meningitis in HIV patients.

Histoplasma capsulatum

Cave exposure, bat or bird droppings, pneumonia-like symptoms.

Haemophilus influenzae

Meningitis, epiglottitis ("thumbprint sign"), pneumonia in kids.

Helicobacter pylori

Epigastric pain relieved by eating, ulcers, chronic gastritis, breath test positive.

Listeria monocytogenes

Unpasteurized dairy, deli meats, pregnancy complications, neonatal meningitis.

Neisseria meningitidis

College dorm outbreaks, fever + stiff neck + petechial rash.

Pseudomonas aeruginosa

Burn patients, blue-green wound pus, fruity smell, hot tub folliculitis.

Shigella

Bloody diarrhea, cramps, daycare outbreaks, fecal-oral spread.

Neisseria gonorrhoeae

Painful urination, purulent discharge, PID, neonatal conjunctivitis.

Bacillus anthracis

Black eschar, animal hides, bioterrorism.

Clostridium botulinum

Flaccid paralysis, canned foods, infant floppy baby syndrome (honey).

Clostridium tetani

Puncture wound, muscle spasms, lockjaw, risus sardonicus.

Streptococcus mutans

Dental plaques, cavities.

Streptococcus pneumoniae

Rust-colored sputum, pneumonia, otitis media, meningitis.

Streptococcus pyogenes

Strep throat, scarlet fever, strawberry tongue, rheumatic fever risk.

Cryptosporidium parvum

Watery diarrhea, contaminated water, AIDS patients severe infection.

Entamoeba histolytica

Bloody diarrhea, liver abscess ("anchovy paste"), travel history.

Toxoplasma gondii

Cat litter, pregnancy risk, ring-enhancing brain lesions in HIV.

Fifth disease (Parvovirus B19)

"Slapped cheek rash" in kids, arthralgias in adults.

Hepatitis (A/B/C)

Jaundice, RUQ pain, elevated liver enzymes.

Herpes simplex virus I/II

Painful vesicles, oral (HSV-1) or genital (HSV-2), latent recurrences.

HIV

Opportunistic infections, chronic weight loss, fever, decreased CD4 count.

Human papillomavirus (HPV)

Warts, cervical dysplasia, sexually transmitted.

Roseola (HHV-6)

High fever followed by rash in toddlers.

Rotavirus

Severe diarrhea in infants/young children, daycare outbreaks.

Ascaris lumbricoides

Intestinal obstruction, worms seen in stool, travel.

Hookworm

Walking barefoot → rash on feet, anemia, GI issues.

Taenia

Eating undercooked pork/beef, proglottids in stool, weight loss.