There was a lot of interest in in TDR-TB Friday; both The Leonard Lopate Show on WNYC and Science Friday kindly asked me to be on to talk about it. While I was waiting for the phone link to Science Friday to become live, an alarming bulletin arrived in my e-mail. The early-warning list ProMED reported that the existence of two additional cases of TDR-TB have been disclosed, in Bangalore, 600 miles from Mumbai where the first known Indian cases were identified. The patients, a 56-year-old man and a 29-year-old woman, had been coming to a hospital for directly observed administration of their TB for more than two years; they were initially recognized as MDR-TB patients, with disease that was highly resistant but not untreatable, but were not getting better. For the past two weeks, though, the man has not shown up, and no one appears to know where he is.
Totally Resistant TB: Earliest Cases in Italy
A follow-up to Monday’s post on the recognition in India of totally drug-resistant tuberculosis, TDR-TB: The fantastic early-warning list ProMED points out that the earliest recorded cases of TDR were not the current 12 known cases in Mumbai or the 15 cases in Iran in 2009, but rather two women from Italy who died in 2003 after being sick for several years.
It’s a sad story that was briefly recounted in 2007 in the journal EuroSurveillance, published by the European Centre for Disease Prevention and Control (ECDC).
Back again to MRSA in animals, and spreading to humans
There are two new reports out regarding new findings of “pig MRSA” ST398 (about which we have talked a lot; archive of posts here.)
First, researchers from the Complejo Hospitalario Universitario de Vigo and Complejo Hospitalario de Pontevedra, both in Pontevedra in northwest Spain, report that they have identified that country’s first human cases of infection with ST398. (It was only last fall that Spain reported the first identification of the strain in animals.)
The age of the three patients was 59, 82, and 83 years, respectively. Two patients owned pigs and the other a calf. Two patients were diabetic and were hospitalized because they developed skin and soft-tissue infections by MRSA ST398. The third patient had bronchitis and the strain was isolated from a respiratory secretion submitted to the laboratory from an outpatient clinic. The three patients had had multiple hospital admissions in the last 12 months.
Tellingly, the researchers spotted these particular isolates (out of 44 analyzed at the two hospitals in 2006) because they were resistant to tetracycline. Tetracycline resistance is not common among community strains of MRSA, because the drug isn’t the first-line choice for skin and soft-tissue infections; and when it is given, it’s usually for a short course, so the drug does not exert much selection pressure on the bug. But tetracycline is a very common animal antibiotic, and tetracycline resistance is a hallmark of ST398; it is one of the factors that led the Dutch researchers who first identified the strain to take a second look at the bug.
Second, researchers from several institutions in Italy report a very troubling case of ST398 infection that produced necrotizing fasciitis — better known as flesh-eating disease. [Read more…]