Chronic Idiopathic Cough
Chronic idiopathic cough may be a distinct clinical entity with an as-yet unidentified cause, a retrospective study suggests.
Of 100 patients referred for chronic cough, 42 had a primary diagnosis of chronic idiopathic cough (CIC). Compared with patients who had other diagnoses, such as postnasal drip, gastroesophageal reflux, and asthma, these patients had a longer median duration of cough (72 vs. 24 months) and were significantly more likely to have had an upper respiratory tract infection as the initial trigger of the cough (48% vs. 24%), Rubaiyat A. Haque, M.B., and colleagues at the Imperial College of London reported.
Furthermore, the CIC patients had significantly greater cough sensitivity, as measured by median log concentrations of capsaicin required to induce five coughs (−0.009 vs. 0.592), the investigators noted (Chest 2005;127:1710–3).
The study population represents patients who had been difficult to diagnose. Therefore, CIC is overrepresented in the sample; CIC patients actually make up a very small subgroup among chronic coughers, the investigators noted. However, the findings suggest a pattern—defined by upper respiratory tract infection history, long cough history, and heightened cough sensitivity—that indicates a distinct clinical entity of CIC, which may be a variation of “postviral cough,” they concluded.
Contaminated Basil
Contaminated fresh basil was the cause of nearly 300 recent cases of cyclosporiasis in Florida, according to the U.S. Food and Drug Administration.
The FDA is conducting a trace-back investigation to locate the source of the basil. The Florida Department of Health reported 293 laboratory-confirmed cases in 32 Florida counties, including several clusters and numerous sporadic cases.
The gastrointestinal infection results from ingestion of the Cyclospora parasite and is associated with watery diarrhea and frequent, explosive bowel movements. Loss of appetite, substantial weight loss, stomach cramps, nausea, vomiting, muscle aches, low-grade fever, and fatigue can also occur, usually within a week of consuming the contaminated food. The symptoms can last for a month or more if untreated.
Tonsillopharyngitis Rx
The optimal dose of azithromycin for the treatment of group A streptococcal tonsillopharyngitis in adults is 500 mg/day for 3 days, a metaanalysis of randomized controlled trials suggests.
A total of 19 trials involving 4,626 patients were included in the analysis. The trials compared various 10-day drugs and two different azithromycin doses and treatment durations, Janet R. Casey, M.D., and Michael E. Pichichero, M.D., of the University of Rochester Medical Center (N.Y.), reported.
In the adult trials, a 30-mg/kg dose of azithromycin (over 3 or 5 days) was comparable to the 10-day drugs (odds ratio 0.86). The 5-day Z Pak (500 mg/day) course of azithromycin approved in the United States was inferior to the 10-day drugs (OR 0.41), but a 3-day course approved outside the United States with the same total dose showed a slight trend toward superiority over the 10-day medications (OR 1.87) (Clin. Infect. Dis. 2005;40:1748–55).
Shorter-course, higher-dose treatment with azithromycin is associated with better bacterial cure rates, and, because longer treatment regimens appear to be associated with poor treatment compliance and thus with treatment failures, it is the preferred approach for treatment of patients with GAS tonsillopharyngitis, the investigators concluded.
Coccidiomycosis Cases
A significant increase in coccidiomycosis cases in Arizona between 1998 and 2001 is attributable to climatic factors, an investigation revealed.
In 1998 there were 33 cases of the disease, also known as valley fever, per 100,000 population; in 2001 there were 43 cases per 100,000 population. The disease has previously been linked to soil disruption, construction, and even earthquakes. In this study, certain climatic and environmental factors (particularly hot and dry conditions) were strongly associated with outbreaks, Benjamin J. Park, M.D., of the Centers for Disease Control and Prevention, Atlanta, and his colleagues reported.
Known risk factors for infection were not significantly more prevalent during the high- vs. low-incidence periods, the investigators noted (J. Infect. Dis. 2005;191:1981–7).
The findings could help public health officials predict seasonal outbreaks of the disease, which is associated with considerable morbidity and a substantial public health burden and allow for the use of appropriate preventive measures, they concluded.
Sharon Worcester