Re: Manjul Tripathi

Pharyngitis is one of the leading reason for physician visits by adults world wide. Approximately 10% of adults with pharyngitis who are seen by physicians are infected with group A Streptococcus (GAS)--the only etiology for which antibiotic treatment is currently acceptable. However, almost three-quarters of all patients with pharyngitis who present for medical care continue to receive antibiotics. In addition, doctors frequently prescribe broad-spectrum antibiotics, including the newer macrolides, although GAS remains sensitive to penicillin and is increasingly resistant to macrolides.

Guidelines from expert panels are shifting away from recommending positive culture results before antibiotic treatment and toward using clinical criteria and/or rapid testing for GAS (followed by confirmatory culture if the rapid test is negative). Neuner and colleagues (2003) conducted a cost-effectiveness analysis of five pharyngitis management strategies and studied the impact of a decision rule on those strategies. The five strategies chosen were observation only; empirical treatment with no testing; throat culture for all patients, with treatment for GAS-positive results; optical immunoassay (OIA) rapid testing, culture for negative results, and treatment for any positive result; and OIA alone, with treatment for positive results.

The baseline prevalence of GAS infection in pharyngitis was 9.7%. At this prevalence, the culture strategy was most effective and least expensive; it was followed in efficacy (in order) by OIA/culture, OIA alone, and observation. Empirical therapy was notably less effective than the other four strategies. The OIA/culture strategy was twice as expensive per patient as culture alone. For any prevalence between 6 and 20%, the culture strategy was most effective and least expensive. Only when OIA specificity was >98% did it become the more effective strategy, but culture remained least expensive at all specificity ranges. Only if the prevalence of GAS pharyngitis exceeded 71% would empirical treatment become the least expensive strategy. This point might be relevant if a highly predictive clinical decision rule was first applied to an individual patient.

This study supports the continued use of throat culture before the treatment of pharyngitis in adults as the most effective and least expensive approach. OIA with or without culture is more expensive but clinically effective. Empirical treatment at current prevalence rates of GAS pharyngitis is not recommended.

In an accompanying editorial, Bisno (2003) notes that the American College of Physicians has accepted the use of a clinical algorithm as a substitute for any microbiological testing in making decisions about the treatment of acute pharyngitis in adults. The American Academy of Family Physicians and the Centers for Disease Control and Prevention are supportive of this approach. In the study by Neuner's group, empirical treatment remained less effective and more expensive than other strategies, even when the best algorithm was used. Culture alone was most effective at the present U.S. prevalence of GAS pharyngitis. Because treatment has a minimal impact on clinical symptoms and contagion, and because suppurative or nonsuppurative sequelae are currently rare, the main goal in managing acute pharyngitis in adult patients should be to reduce the inappropriate use of antibiotics, particularly given the trend of physicians to prescribe broad-spectrum antibiotics. The Infectious Diseases Society of America now recommends the use of rapid antigen testing so that a decision regarding antibiotic treatment can be made quickly before the patient leaves the doctor's office. This approach is consistent with the study by Neuner and colleagues, which finds it to be as effective as culture alone, although more expensive. In any event, Bisno concludes that some testing should be performed; if treatment is indicated, penicillin is the drug of choice for nonallergic patients.

Having said the above, if treatment still fails, a re-evaluation of the the patient (in this case, your sister) should be done as the initial diagnosis maybe wrong. A step-wise approach should be taken and investigations retaken. Keep an open mind as to the diagnosis and keep looking out for differential diagnosis, as a once famous professor said - the eyes does not see what the mind does not know. :) Hope this helps and sorry for the extremely late reply. All the best in the recovery of your sister. God bless.