Classic Labs/findings part 1 Flashcards
Colonies of mucoid Pseudomonas in lungs
Cystic fibrosis (autosomal recessive mutation in CFTR gene --> fat-soluble vitamin deficiency and mucous plugs)
Decreased AFP in amniotic fluid/maternal serum
Down syndrome, Edwards syndrome
Increased β-hCG,
Decreased PAPP-A on first trimester screening
Down syndrome
Increased serum homocysteine, increased mehtylmalonic acid, decreased folate
Vitamin B12 deficiency
Anti-histone antibodies
Drug-induced SLE (eg, hydralazine, isoniazid, phenytoin, TNF-α inhibitors)
Low T cells, low PTH, low Ca2+, absent thymic shadow on CXR
Thymic aplasia (DiGeorge syndrome, velocardiofacial syndrome)
Large granules in phagocytes, immunodeficiency
Chédiak-Higashi disease (congenital failure of phagolysosome formation)
Recurrent infections, eczema, thrombocytopenia
Wiskott-Aldrich syndrome
Optochin sensitivity
Sensitive: S pneumoniae;
Resistant: viridans streptococci (S mutans, S sanguis)
Novobiocin response
Sensitive: S epidermidis;
Resistant: S saprophyticus
Bacitracin response
Sensitive: S pyogenes (group A);
Resistant: S agalactiae (group B)
Branching gram ⊕ rods with sulfur granules
Actinomyces israelii
Hilar lymphadenopathy, peripheral granulomatous lesion
in middle or lower lung lobes (can calcify)
Ghon complex (1° TB: Mycobacterium bacilli)
“Thumb sign” on lateral neck x-ray
Epiglottitis (Haemophilus influenzae)
Bacteria-covered vaginal epithelial cells
“Clue cells” (Gardnerella vaginalis)
Dilated cardiomyopathy with apical atrophy
Chagas disease (Trypanosoma cruzi)
Atypical lymphocytes, heterophile antibodies
Infectious mononucleosis (EBV infection)
Eosinophilic intranuclear inclusions with perinuclear
halo
Cells infected by herpesviruses (eg, HSV, VZV, CMV)
“Steeple” sign on frontal CXR
Croup (parainfluenza virus)
Eosinophilic inclusion bodies in cytoplasm of
hippocampal and cerebellar neurons
Negri bodies of rabies
Ring-enhancing brain lesion on CT/MRI in AIDS
Toxoplasma gondii, CNS lymphoma
Psammoma bodies
Meningiomas, papillary thyroid carcinoma,
mesothelioma, papillary serous carcinoma of the
endometrium and ovary
“Delta wave” on ECG, short PR interval, supraventricular
tachycardia
Wolff-Parkinson-White syndrome (bundle of Kent
bypasses AV node)
“Boot-shaped” heart on x-ray
Tetralogy of Fallot (due to RVH)
Rib notching (inferior surface, on x-ray)
Coarctation of the aorta
Granuloma with giant cells after pharyngeal infection
Aschoff bodies (rheumatic fever)
Electrical alternans (alternating amplitude on ECG)
Cardiac tamponade
Enlarged thyroid cells with ground-glass nuclei with central clearing
“Orphan Annie” eyes nuclei (papillary carcinoma of the
thyroid)
“Brown” tumor of bone
Hyperparathyroidism or osteitis fibrosa cystica (deposited hemosiderin from hemorrhage gives brown color)
Hypertension, hypokalemia, metabolic alkalosis
1° hyperaldosteronism (eg, Conn syndrome)
Mucin-filled cell with peripheral nucleus
“Signet ring” (gastric carcinoma)
Anti-transglutaminase/anti-gliadin/anti-endomysial
antibodies
Celiac disease (diarrhea, weight loss)
Narrowing of bowel lumen on barium x-ray
“String sign” (Crohn disease)
“Lead pipe” appearance of colon on abdominal imaging
Ulcerative colitis (loss of haustra)
Thousands of polyps on colonoscopy
Familial adenomatous polyposis (autosomal dominant, mutation of APC gene)
