Jay B. Mehta

Prosthetic joint infection by Mycobacterium tuberculosis : An unusual case report with literature review

Prosthetic joint infection with Mycobacterium tuberculosis usually involves the hips or knees and can result from either local reactivation, or less often from hematogenous spread. Predisposing conditions include rheumatoid arthritis, chronic steroid use and pulmonary diseases. The most common symptom at presentation is pain, and the most common physical finding is joint swelling and/or a draining sinus tract. The sedimentation rate is helpful when elevated but is nonspecific, and initial skin testing is only helpful when positive. The diagnosis depends on culture and histologic examination of tissue. Removal of the joint combined with oral antituberculous treatment is necessary when the infection is discovered greater than six weeks post joint replacement. Early diagnosis leads to decreased morbidity. Tuberculous infection of prosthetic joints is a rare disease and its diagnosis depends on a high degree of clinical suspicion.

Atypical Pott's disease: localized infection of the thoracic spine due to Mycobacterium avium-intracellulare in a patient without human immunodeficiency virus infection.

Mycobacterium avium-intracellulare (MAI) rarely causes disease of the spine in healthy individuals. We describe an elderly woman who had isolated skeletal involvement with MAI, mimicking Potts disease. She responded well to surgical excision of the inflamed tissue and antibiotic therapy. Osteomyelitis due to MAI must be differentiated from that due to Mycobacterium tuberculosis because the treatment regimens are different.

Peritoneal tuberculosis: modern peril for an ancient disease.

Extrapulmonary manifestations of Mycobacterium tuberculosis (MTB) in general, and tuberculous peritonitis (TBP) in particular, have posed complex diagnostic challenges for centuries. Peritoneal tuberculosis is a very rare manifestation of MTB with subtle clinical findings that may result in a significant diagnostic delay, often of more than four months. As the incidence of tuberculosis is declining in developed nations, clinicians may overlook the need to establish an early diagnosis and prompt therapy for this disorder. We present a case of peritoneal tuberculosis and a review of the literature.

Mycobacterium xenopi Pneumonia in the Southeastern United States

Mycobacterium xenopi (M. xenopi) is a slow-growing, nontuberculous mycobacterium (NTM). This organism is found in fresh water and has been isolated in water samples collected from water systems in homes and hospitals. Before the acquired immunodeficiency syndrome epidemic, M. xenopi infection was infrequent and occurred in clusters; however, M. xenopi is now a recognized cause of pulmonary infection in immunocompetent patients with preexisting lung disease. The classic chest x-ray appearance is cavitary apical pulmonary disease, which mimics tuberculosis. M. xenopi is currently one of the most common NTM pathogens in parts of England and Canada and has been reported in parts of the northeastern United States. Whether the isolation of M. xenopi from our patient in Tennessee represents a new geographic distribution of this organism or technologic advancements that now allow for reliable identification is debatable. This case serves as a reminder to clinicians that the incidence of NTM infection is rising in the United States and that unusual NTM are capable of causing disease even in patients who are not immunocompromised.

All-trans retinoic acid syndrome : Another cause of drug-induced respiratory failure

It is now possible to achieve complete remission in the majority of patients with acute promyelocytic leukemia (APL) if all-trans retinoic acid (ATRA) is administered as a single agent or in combination with cytotoxic chemotherapy. Despite its positive influence on recovery, ATRA is not without the potential for toxicity. It is important for clinicians participating in the care of patients undergoing treatment with this drug to be aware of ATRA syndrome and institute the appropriate therapy to reduce the likelihood of an adverse outcome.

Chemotherapy of Tuberculosis in Developed Countries

The chemotherapeutic era of tuberculosis began with the discovery of streptomycin (SM) in 1944 and its trial in 1945 (1,2). Soon after the introduction of isoniazid (INH) in 1952 (3), drug therapy was adopted as an important weapon in the treatment of this ancient disease. In the early stages of chemotherapy, it became apparent that drug resistance and treatment failure resulted when monotherapy with SM was used to treat active disease harboring large bacillary populations (4). The addition of a second drug to the regimen, such as para-amino-salicylic acid (PAS) or INH, prevented the emergence of drug resistance and treatment failure (5,6). Soon, the efficacy of chemotherapy was firmly established. Provided that the appropriate drug combinations were utilized against susceptible pretreatment organisms, tuberculosis could be cured within 18–24 months.