Treating Subclinical Hypothyroidism in Seniors

SOURCE: Stott DJ, Rodondi N, Kearney PM, et al. Thyroid hormone therapy for older adults with subclinical hypothyroidism. N Engl J Med 2017;376:2534-2544.

Subclinical hypothyroidism (SCH) is defined as an elevation in thyroid-stimulating hormone (TSH) in the presence of normal levels of thyroxine. When thyroxine drops to subnormal levels in the company of elevated TSH, primary hypothyroidism is diagnosed. Since SCH often is a stepping stone to overt hypothyroidism, it is tempting to offer treatment for it. But does treatment of SCH improve outcomes?

By definition, patients with SCH are not supposed to be symptomatic of hypothyroidism; otherwise, the syndrome could not be called “subclinical.” But might restoration of full chemical euthyroid status provide a boost to energy, well-being, or other quality-of-life attributes? Stott et al performed a double-blind, randomized, controlled trial in older adults (mean age = 74 years) with SCH comparing levothyroxine supplementation to placebo (n = 737). Outcomes at one year included hypothyroid symptom scores, fatigue measurements, and quality-of-life outcomes.

Although levothyroxine supplementation provided meaningful reductions of TSH into the normal range, there was no statistically significant improvement in any of the symptom outcomes. Additionally, since levothyroxine supplementation proved quite safe, these data should discourage clinicians from treating elevations of TSH unless thyroxine levels also are subnormal.

The Mistaken ‘Penicillin Allergy’ Label

SOURCE: Trubiano JA, Adkinson NF, Phillips EJ. Penicillin allergy is not necessarily forever. JAMA 2017;318:82-83.

Although they should be applauded for their perspicacity in identifying drug allergies among their patients, the literature suggests clinicians have grossly overestimated the actual prevalence of penicillin allergies. Based on sophisticated diagnostic testing, only 1% of the U.S. population actually is allergic to penicillin, yet as many as 10% of Americans have been labelled as penicillin-allergic.

It is easy to understand how a rash appearing after a viral infection during which penicillin had been inappropriately administered might prompt the belief that the antibiotic was the culprit. Additionally, even when IgE-mediated reactions to penicillin occur, reactivity appears to wane over time, such that most patients who have manifested penicillin allergies will exhibit negative penicillin skin test reactions 10 years later.

Further, these same individuals who become penicillin skin-test negative are reported to have minimal future risk of reacting to penicillin or other beta-lactam antibiotics.

In an era requiring more vigilant antibiotic stewardship, clarifying whether a patient who reportedly suffers from penicillin allergies actually still has that hyperreactivity through skin testing may allow us to be more focused in our choice of penicillins and cephalosporins.

Updates on Diverticulitis Guidance

SOURCE: Shah SD, Cifu AS. Management of acute diverticulitis. JAMA 2017;318:291-292.

Only a small fraction of patients with diverticular disease of the colon ever incur diverticulitis. That is, although as many as 60% of patients > 60 years of age have diverticuli, only 4% of them get diverticulitis. Much of the advice about treatment and prevention of diverticulitis and its recurrence has been based on opinion and/or low-quality evidence.

Some previously fundamental precepts, such as the universal need for antibiotic treatment in acute diverticulitis and suggested dietary alterations (e.g., increased fiber and avoidance of nuts, seeds, or popcorn) for prevention, are called into question by this most recent American Gastroenterological Association review.

Although “high-risk” groups who merit antibiotic administration are delineated (for instance, immunocompromised, significant comorbidities, pregnancy, sepsis), whether antibiotics improve outcomes in other populations with acute uncomplicated diverticulitis is much more uncertain.

Evolving insight into the pathology of acute diverticulitis is refocusing on inflammatory aspects of the disorder, as opposed to infectious links. Much uncertainty still surrounds the etiology and best management of acute diverticulitis.