23 - 152 - GRAM-POSITIVE INFECTIONS ASSOCIATED WITH TOXIN PRODUCTION Flashcards
What toxins can cause bullous impetigo and staphylococcal scalded skin syndrome?
Exfoliatin Type A (ETA) and ETB
Toxin that causes toxic shock syndrome (menstrual»nonmenstrual)
Toxic shock syndrome toxin 1 (TSST-1)
Toxins that can cause scarlet fever
Streptococcal pyrogenic exotoxins A and C ( SPEA, SPEC)
The epidermolysis in SSSS usually occur where?
between the stratum spinosum and granulosum
T/F. Nikolsky sign is positive in SSSS
True
2 forms of exfoliatin-mediated disease:
localized bullous impetigo and systemic SSSS
In both bullous impetigo and SSSS, the intraepidermal cleavage induced by the epidermolytic toxin occurs within or just below the stratum __________.
granulosum
Major complications of SSSS
serious fluid and electrolyte disturbances
The most common staphylococcal toxin associated with TSS is ________ and is the predominant toxin associated with menstrual-associated cases.
TSS toxin-1 (TSST-1)
predominant toxin associated with menstrual-associated cases.
Clinical manifestations of toxic shock syndrome
- The symptoms of TSS begin with acute onset of fever, sore throat, and myalgia.
- Diarrhea is common, and vomiting may also occur.
- The rash is most often a macular erythema but a scarlatiniform type can sometimes be seen.
- The eruption usually begins on the trunk and spreads to the extremities, and can involve palms and soles.
- Especially if the patient is hypotensive, the eruption tends to be more prominent on the trunk than extremities.
- Symptoms of hypotension include** orthostatic dizziness, fainting, and overt shock.**
- Nonpurulent conjunctival hyperemia,** pharyngeal inflammation and strawberry tongue** are invariably present.
- Signs of decreased mentation can also occur.
- The rash will desquamate within 1 to 2 weeks after beginning.
Major criteria of Staphylococcal Toxic Shock Syndrome
streptococcal TSS has been well-described as a complication of what viral illnesses?
Varicella and Influenza A
T/F. A patient with signs of TSS and a localized cellulitis should suggest STREPTOCOCCAL TSS, as soft-tissue infections are not usually seen with STAPHYLOCOCCAL TSS.
TRUE
how can you differentiate kawasaki from toxic shock syndrome since they may have similar clinical findings, including swelling of extremities and desquamation of palms and soles during convalescence?
Kawasaki syndrome differs in that the course of fever is prolonged and diarrhea and hypotension are absent.
Clinical findings of recalcitrant erythematous, desquamating disorder (REDD)
fever and hypotension
The rash of REDD consists of diffuse macular erythema with delayed desquamation. Other findings in common with TSS include ocular and oral mucosal injection and strawberry tongue.
Scarlet fever is a syndrome characterized by
exudative pharyngitis, fever, and scarlatiniform rash
Clinical manifestations of streptococcal scarlet fever
Approximately 12 hours to 5 days after exposure, an abrupt prodrome consisting of pharyngitis, headache, vomiting, abdominal pain, and fever develops. The rash appears 1 to 2 days after onset of the illness, first on the neck and then extending to the trunk and extremities, although sparing the palms and soles.
The exanthem texture is usually coarse like fine-grade sandpaper, and the erythema blanches with pressure. The skin can be mildly pruritic, but usually is not painful.
In streptococcal scarlet fever, A few days following generalization of the exanthem, it becomes more intense around skinfolds and lines of confluent petechiae resulting from increased capillary fragility can be seen.
What do you call this sign?
Pastia sign
In strep scarlet fever, The generalized exanthem begins to fade _______ days after onset and a desquamative phase begins, usually starting with the face. Peeling from the palms and fingers and sometimes soles occurs approximately a week later and can last for as long as 1 month.
3 to 4 days
Oral findings of streptococcal scarlet fever include
edematous, erythematous tonsils sometimes covered with a yellow, gray, or white exudate and tender anterior cervical lymphadenopathy is common
What do you call the Petechiae and punctuate red macules are seen on the soft palate and uvula seen in strep scarlet fever?
Forchheimer spots
Characteristic changes of the tongue in strep scarlet fever
During the first 2 days of the disease, the tongue has a white coat through which the red and edematous papillae project (white strawberry tongue). After 2 days, the tongue desquamates resulting in a red tongue with prominent papillae (red strawberry tongue).
How can you differentiate Scarlet fever induced by staphylococci from those caused by strep?
LACK OF PHARYNGITIS
How can you differentiate kawasaki from Staphylococcal scarlet fever?
Although Kawasaki syndrome has many similar clinical findings, including mucosal involvement (eg, strawberry tongue), and swelling of extremities and desquamation of palms and soles during convalescence, Kawasaki syndrome differs in that the course of fever is prolonged and cultures would be expected to be negative.
What clues should you look for to differentiate scarlet fever caused by staph and strep
Scarlet fever from group A Streptococcus can usually be differentiated from that induced by S. aureus as the usual nidus of infection in streptococcal scarlet fever is from a pharyngitis whereas the staphylococcal variant usually has its infectious nidus in the skin.
characterized by a striking diffuse macular perineal erythema that occurs within 24 to 48 hours after a pharyngitis with a toxin-producing group A Streptococcus or S. aureus
Recurrent toxin-mediated perineal erythema
The majority of cases of streptococcal TSS are caused by what superantigen?
streptococcal pyrogenic exotoxin A (SPEA)
Features of Staphylococcal Scalded Skin Syndrome
- Affected individuals initially exhibit a faint, orange-red macular exanthem sparing mucosal surfaces in association with a purulent conjunctivitis, otitis media, nasopharyngeal infection or occasionally pyogenic skin infection such as from an umbilical stump or boil (carbuncle)
* Periorificial and flexural accentuation of the exanthema is often noted. - concomitant cutaneous tenderness is usually present at early stage
