We spoke today about Group A Streptococcus (Streptococcus pyogenes).  I thought it would be reasonable to quickly review rheumatic fever (see review).

Diagnosis (Jones Criteria):

MAJOR:
Carditis

• Can affect pericardium, myocardium, endocardium, and epicardium.  Pericardium:  pleuritic chest pain, pericarditis.  Endocardium: usually new mitral regurgitation.  Epicardium:  Conduction abnormalities.  Myocardium:  Can mimic myocarditis.

Polyarthritis

• Knees, elbows, ankles, wrists.  Often overlapping and migratory.

Chorea

• Often unilateral chorea.  Emotional lability.  Weakness.  Sensory change is not seen.

Erythema marginatum

• Evanescent, pink rash with circumsribed borders.  Usually on trunk/arms.

Subcutaneous nodules

• Painless with normal overlying skin on bony surfaces and tendon.  A few mm to 1cm in size. Usually 3-4 and symmetric.

MINOR
Arthralgia
Fever
Elevated CRP
Prolonged PR interval

Diagnosis:  2 major or 1 major 2 minor.  Debate as to how sensitive these criteria are -- and they may lead to undertreatment/diagnosis.

Note:  At time of diagnosis up to 75% will be culture negative.  Usually happens about 2-3 weeks post infection.  The ASOT can be helpful (but isn't perfect and many labs don't do it anymore) particularly if it rises with 2 samples taken 2 weeks apart. 

See previous blog about peripartum sepsis and toxic shock syndrome including treatment thereof.

See necrotizing fasciitis described in this blog including role of IVIG and prophylaxis of close contacts.

Penicillin Allergy

Not to be understated in terms of potential severity, it is true that the number of penicillin 'allergic' patients far outnumbers the number of patients with an actual allergy to penicillin.

The validity of allergies to penicillin recorded in the chart is questionable. The JAMA classic article on history of pencillin allergy is here.

This study (and others) shows meropenem is *likely* safe in patients with IgE mediated penicillin allergy.

The following review article discusses the use of other agents and a strategy for evaluating patients with penicillin allergy. This review discusses antibiotic allergies in general.

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The ACLS guidelines for the management of anaphalaxis are here.

Delusional Parasitosis

Interesting case today -- and sad. Delusional parasitosis can be very difficult to treat and can be debilitating for patients. There is a role for consult liason psychiatry and newer generation antipsychotics (see review here).

An interesting case report of IATROGENIC delusional parasitosis (i.e. patient believed she had infestation because her doctors told her she did) is here.

Surgery for Infective Endocarditis

Recent publication in circulation addresses the issue very well.

For the cutting edge -- vegetectomy (removal of vegetation) without valve replacement may be an option worthy of study.

See previous posts on IE for more info on IE.

PCP with steroids

Frequently invoked, rarely proven the development of PCP with steroid therapy is rare but important to consider.

TMP/SMX prophylaxis for PCP in patients on high dose steroids (see the table contained within) from this meta-analysis. In general, though there is no consensus, PCP prophylaxis should be considered in patients on greater than 30mg of prednisone for greater than three months or those who are on moderate-high dose steroids with another immunosuppressive agent (i.e. patients with Wegner's)

However, the story may be different in lymphoma treatment, particularly with rituximab and high dose CHOP therapy but overall is also low in hematologic (exclude ALL) and solid organ malignancy.

Vancomycin Nephrotoxicity

A review of vancomycin nephrotoxicity is available here.

The IDSA guidelines for therapeutic drug monitoring of vancomycin here.

The first vancomycin trough achieved seems to have predictive value for who will develop nephrotoxicity.

The role of dialysis in acute vancomycin mediated renal injury is discussed here (little evidence from which to draw conclusions, but seems reasonable).