Pulmonary tuberculosis sustained by Mycobacterium bovis in a young Italian patient-e289

The Mycobacterium tuberculosis complex (MTBC) includes M. tuberculosis, M. bovis, M. bovis bacillus Calmette-Guérin (BCG, the vaccine strain), M. africanum, and M. microti. Mycobacterium tuberculosis causes the majority of tuberculosis (TB) cases in humans; however, in several regions of the world, especially in a country with high prevalence of HIV infection, human TB caused by M. bovis may be common but underreported1. M. bovis is the main cause of tuberculosis in cattle, deer, and other mammals and human pathology is considered a zoonosis; transmission is mainly through consumption of unpasteurized dairy products, and it is less frequently attributed to inter-human transmission. The exact incidence of M. bovis TB is uncertain but it is considered to be uncommon in rich-resource countries; worldwide it is estimated to be responsible for approximately 3% of pulmonary tuberculosis2. We report the case of an Italian woman in her thirties; she reported no history of travel outside Western Europe, no contact with subjects with active pulmonary tuberculosis or chronic cough. Her past medical history included an episode of acute pyelonephritis and Gilbert’s pityriasis rosea but no other significant condition or hospital admission. She reported two weeks of night sweats, malaise and productive cough (following six months of dry cough); after the sudden onset of haemoptysis she presented to the emergency room. Chest X-ray and computerized tomography showed bilateral lung infiltrates with multiple cavitations (Figure 1) but the smear tested negative for alcohol-acid resistant bacilli. Given the high suspicion she was admitted to our Infectious Disease ward and placed in respiratory isolation with negative pressure aspiration. Physical examination at admission was insignificant with a body temperature of 37.3 °C, blood pressure of 110/70 mmHg, a pulse rate of 74/minute and a respiratory rate of 24/min. Physical examination of the chest, head, neck, lymph nodes, heart and abdomen was normal. ABSTRACT: — Historically, Mycobacterium bovis infection in humans was associated with consumption of unpasteurized milk and dairy products and this is still the most important route of exposure in limited-resource countries; in rich resource countries, this infection has been usually observed in elder subjects. Direct airborne transmission from animals to humans is thought to be a rare as well as an interhuman transmission. We here describe the diagnosis and clinical management of pulmonary M. bovis infection in a 30-year-old healthy Italian female patient. One interesting aspect of this case is the absence of identifiable risk factors including the consumption of unpasteurized diary products or animal contact. Being M. bovis usually resistant to pyrazinamide, it is important to understand the epidemiology of human Mycobacterium bovis tuberculosis in order to personalize anti tubercular treatment.