Micro

Question 1

Mother to Child HIV Vertical Transmission

Answer 1

• CP: oral thrush, intestinal pneumo, severe lymphopenia
• Tx: ART reduce risk: 1-2%

Question 2

Viral Vaccines

Answer 2

• inactivated (killed or component)
  
  • mostly generate a humoral response
• live-attenuated
  
  • generate STRONG cell-mediated immune response IN ADDITION to humoral immunity

Question 3

Mucormycosis

Answer 3

• opportunistic infection caused by Rhizopus, Mucor, …..sp
• CP: paranasal sinus involvement in a diabetic or immunosuppressed pt
• fungi: broad non-septate hyphae that branch at right angles

Question 4

HBV infection

Answer 4

• can produce 1 of 3 syndromes:

1. acute hepatitis with complete resolution (>95% adults)
2. chronic hepatitis
   
   1. with or without cirrhosis and the attendant increased risk of hepatocellular carcinoma
3. fulminant hepatitis with massive liver necrosis

Question 5

EBV

Answer 5

• has mononucleosis-like serum heterophile Ab
  
  • CP: fever, fatigue, splenomegaly, atypical lymphocytosis
• oncogenic virus**
• CP: lymphadenopathy, sore throat
• commonly infect (polyclonal) B-cells and stimulate them to proliferate continuously (transformation/immortalization)
• Test: heterophile Ab test (sn and sp)

Question 6

CMV

Answer 6

• acquired during transfusion of leukocyte laden blood products
• infects leukocytes of granulocyte-macrophage lineage

Question 7

Giardia Lamblia

Answer 7

• causes injury to the duodenal and jejunal mucosa by adhering to the intestinal brush border and releasing molecules that induce a mucosal inflamm response
• secretory IgA which impairs adherance is major component of adaptive immunity vs. G lamblia infection
• conditions causing IgA deficiency predispose pts to chronic giardiasis

Question 8

Disease caused by “exotoxin” relese by S. aureus

Answer 8

• Toxic shock syndrome, staphylococcal scalded syndrome, gastroenteritis
• staphylococcal food poisoning occurs after a food handler inoculates food (usually a mayo-containing product) with S. aureus that is allowed to incubate at room temp producing heat-stable exotoxin that causes rapid-onset nausea, vomiting, and abdo cramping

Question 9

HUS (hemolytic Uremic Syndrome)

Answer 9

• Path: Gi infection: Shiga (E. coli O157:H7)
  
  • toxins injure endothelium of pre-glomerular arterioles and glomerular capilaries
  • gram neg rods from bladder; vesicaureteral reflex (ACUTE pyelonephritis)
  • PMN leukocytes (N) in interstitium and tubular lumina
• Clinical:
  
  • acute RF in young kids; after diarrhea (often bloody)
  • thrombocytopenia
  • microangiopathic HA (conjunctival pallor)
  • acute kidney injury (oliguria/anuria, hematuria, increased Cr
• tx: ECULIZUMAB

Question 10

Strongyloides stercoralis

Answer 10

• hyperinfection syndrome-massive dissemination of the organism leading to multiorgan dysfunction and septic shock

Question 11

Bartonella henselae

Answer 11

• causes cat-scratch dz, bacilliary angiomatosis (in immunocomp pts), and culture-negative endocarditis
• charac: low fever, (tender regional) lymphadenopathy and self-limited course

Question 12

WNV (West Nile Virus)

Answer 12

• positive sense
• singe strand
• flavivirus
• transmitted by: female mosquitos
  
  • mc in the summer
• neuroinvasive dz
  
  • CP: encephalitis, meningitis, or flaccid paralysis
• management: supportive