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Am Fam Physician. 2021;103(3):143

What diagnostic testing should be performed in patients suspected of having Clostridioides difficile?

Clostridioides difficile is challenging to diagnose because of high rates of colonization without disease. A two-step algorithm should be used to guide diagnostic testing for C. difficile infection: enzyme immunoassay for glutamate dehydrogenase and toxins A and B, followed by nucleic acid amplification testing if initial results are indeterminate. For patients likely to have C. difficile infection based on symptoms, either nucleic acid amplification testing or the two-step algorithm can be performed.

Is onabotulinumtoxinA safe and effective at reducing the frequency of migraine headaches in adults?

In adults with chronic migraine, where headaches occur 15 days or more per month, onabotulinumtoxinA (Botox) treatment reduces the number of migraine days by two days per month compared with placebo. Nonserious adverse effects, including neck pain, arm weakness, and blepharoptosis, are more common in patients treated with onabotulinumtoxinA (number needed to harm = 7), but serious adverse effects are not increased.

Is early colonoscopy important in lower gastrointestinal bleeding?

Early colonoscopy (within 24 hours of presentation) is not preferred in hemodynamically unstable patients because it does not improve mortality, adverse events, rebleeding rates, or the need for surgery or blood transfusions over colonoscopy after hemodynamic stability and bowel preparation.

Do exercise interventions in community-dwelling older adults reduce the incidence of falls?

Exercise programs should be recommended for community-dwelling adults 60 years and older because they lead to fewer falls. Community-dwelling adults 50 years and older should participate in exercise programs to decrease their rate of falls resulting in fractures. Balance training, functional exercise, and resistance training are the most effective types of exercise to reduce fall risk.

In what neurologic conditions are short-term systemic corticosteroids appropriate?

Systemic corticosteroids are recommended for patients within three days of the onset of symptoms of Bell palsy. There is insufficient evidence to support the routine use of systemic corticosteroids for patients with lumbar radiculopathy. Do not prescribe systemic corticosteroids as first-line therapy for patients with carpal tunnel syndrome.

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