SGA Resp Micro Deck

Question 1

An eight-year-old boy who was adopted from a developing country and recently migrated to the US, presents with an abrupt onset of fever and sore throat of 24 hours. On examination,** he has bilateral**, greyish white tonsillar exudates, punctate hemorrhages and bilateral, swollen, tender, anterior cervical lymph nodes, T 39oC (102.2oF). Lungs and airways are clear

Which of the following is the most likely causal organisms? justify your answer choice and why the other options are less likely

A. Epstein Barr virus
B. Herpes simplex virus
C. Streptococcus pyogenes
D. Corynebacterium diphtheriae
E. Hemophilus influenzae
F. Streptococcus pneumoniae
G. Candida albicans

Answer 1

C.Streptococcus Pyogenes.
Children (5-15years)
Developr( 2-4 days) post exposure
Clinical Presentations: Sore throat, fever, malaise and headache. Posterior pharynx can appear erythematous with an exudate and cervical lymphadenopathy can be prominent.

Question 2

A viral infection that presents with vesicular mucosal lesions and Ulcers?

Answer 2

Herpes Simplex virus

Question 3

Sudden onset of malaise, sore throat, exudative pharyngitis and low grade fever and a Thick Pseudomembrane* that can cover the tonsils, uvula, and palate and can extend up into the nasopharynx or down into the larynx the pseudomembrane firmly adheres to the underlying tissue and is difficult to dislode without making the tissue bleed?

Answer 3

Diptheria

Question 4

Presents as epiglottitis, massive swelling of epiglottis and obstruction?

Answer 4

Hemophilus Influenzae

Question 5

True or False

Streptococcus pneumoniae is a lower respiratory tract infection pneumonia

Answer 5

True

Question 6

True or False?

Candida Albicans are seen only in Immunocompromised host?

Answer 6

True

Question 7

What test can be used to confirm a diagnosis of Strep throat infection?

Answer 7

A rapid antigen detection test; If test is negative and still suspect a strep, a Throat Swab culture on Blood agar is indicated as this is more sensitive

Question 8

EBV diagnosis can be confirme by?

Answer 8

Monospot test

Question 9

Why is a throat swab gram stain not useful in confirmation of a strep throat?

Answer 9

This is because many other species of streptococcus (Gram positive in chains) are normal throat flora

Question 10

What stain is used for Corynebacterium?

Answer 10

Albert Stain

Question 11

True or False/?

PCR is an expensive test and can be reserved for detecting organisms that cannot be demonstrated or grown in culture

Answer 11

True

Question 12

A boy (8 yrs old) diagnosed with strep pyrogene 3 days later presents with an extensive rash with flaky desquamation of palm and sole, What is the most likely diagnosis?
A. Scarlet fever
B. Kawasaki disease
C. Impetigo
D. Mononucleosis

Answer 12

Scarlet fever

Question 13

What is the diagnosis?

A **diffuse, erythematous, sandpaper like rash initially appears on the upper chest and then spreads to the extremities within1 to 2 days after the initial clinical symptoms of pharyngitis develop. ** Area around the mouth, palm and soles are generally spared (Circumoral pallor), **Yellowish-white coating intially covers the tongue and is later shed, revealing a red, raw surface beneath (Strawberry tongue), RASH blanches when pressed is seen on the abdomen and skin folds (Pastia lines)- Rash disappears over the next 5-7 days and is followed by ** flaky desquamation of the superficial skin layer even in the palm and soles

Answer 13

Scarlet fever

Question 14

Differences between presentations in Kawasaki (Toxin -mediated illnesses) and Scarlet fever (Pharyngitis)

Answer 14

Is that Kawasaki rash is not sandpaper in nature and desquamation in kawasaki usually begins in the periungual region whereas in Scarlet fever, the desquamation tends to be diffsuse and flaking , Kawasaki tens to be sheet-like and prevents with non-exudative conjuctivitis , there are no conjuctivitis in group A strep

Question 15

What skin lesion?

Crusty, weeping, honey colored lesions are seen on the skin

Answer 15

Impetigo

Question 16

Mononucleosis can also present with rash but is unlikely in Children 5-15years> True or False

Answer 16

True

Question 17

besides from scarlet fever which other infectious rash is seen on Palm and Sole?

Answer 17

RMSF (Rocky Mountain spotted Fever)
Syphylis
Toxic shock syndrome

Question 18

Which of the following virulence factor is the most likely cause for the rash and desquamation?

A. M protein
B. Plasmid coded Toxin
C. Toxin, inhibiting protein synthesis
D. Phage coded Super antigen
E. Hyaluronidase

Answer 18

D. Phage coded Super antigen.
Scarlet fever is a complication of streptococcal pharyngitis that occurs when Streptococcus pyogenes (Group A Streptococcus) is lysogenized by a bacteriophage that mediates production of a pyrogenic exotoxin, the streptococcal pyrogenic exotoxins (Spe), originally called erythrogenic toxin,
The toxins act as superantigens, interacting with both macrophages and helper T cells, with the enhanced release of proinflammatory cytokines (superantigen action like TSST, desquamation and rash) recall the presentation of TSS)

Incorrect options:
A. M protein (inhibits phagocytic clearance and complement)
B. Toxin coded by plasmid (ETEC toxin is plasmid coded)
C. Toxin inhibiting protein synthesis (diphtheria toxin)
E. Hyaluronidase (spreading factor