Culture Acid-fast Bacilli Research Articles

An update on lower urinary tract tuberculosis

Tuberculosis of the genitourinary tract presents with atypical manifestations. Only 20% to 30% of patients with genitourinary tuberculosis have a history of pulmonary infection. Tuberculosis often affects the lower genitourinary system rather than the kidney. Tuberculosis of the lower genitourinary tract most commonly affects the epididymis and the testis, followed by bladder, ureter, prostate, and penis. Use of bacillus Calmette-Guérin therapy for bladder cancer can cause symptomatic tubercular infections of the lower genitourinary tract. Tuberculosis of the lower genitourinary tract can present with irritative voiding symptoms, hematuria, epididymo-orchitis, prostatitis, and fistulas. Tuberculosis of the seminal vesicles, vas, fallopian tubes, and the uterus can cause infertility. Urinalysis may demonstrate sterile pyuria, hematuria, or albuminuria. Identification of acid-fast bacilli in culture or tissue or by polymerase chain reaction studies is diagnostic. Medical treatment may not result in resolution of symptoms. Surgical intervention and reconstruction of the urinary tract are frequently indicated.

Tuberculous brain abscess: clinical presentation, pathophysiology and treatment (in children).

Tubercular brain abscess (TBA) is a rare manifestation of CNS tuberculosis. It is characterised by an encapsulated collection of pus, containing viable tubercular bacilli without evidence of tubercular granuloma. PRESENTATION AND HISTORY: Patients may present with features of raised intracranial pressure and focal neurological deficit commensurate with the site of the abscess. A history of pulmonary tuberculosis may be present, as documented in one of our six cases; three of our six children developed TBA despite 3-weeks to 12-month courses of antitubercular chemotherapy prescribed for post-TBM hydrocephalus. Contrast CT head, MRI, MR spectroscopy is helpful in making the diagnosis and planning the treatment. TBA may be unilocular or multilocular on contrast CT scan. A relatively long clinical history and an enhancing capsule with thick wall are suggestive of TBA. Pyogenic abscess, however, has a thin rim on contrast CT. The capsule of TBA is formed of vascular granulation tissue containing acute and chronic inflammatory cells, particularly polymorphs. Proof of tubercular origin must be demonstrated either by presence of acid fast bacilli in culture or staining of pus or wall. Treatment options include simple puncture, continuous drainage, fractional drainage, repeated aspiration through a burr hole, stereotactic aspiration and total excision of the abscess. Total excision usually becomes necessary in multilocular noncommunicating and thick-walled abscesses. Antitubercular therapy is the mainstay of management. The development of fulminant tubercular meningitis is sometimes problematic following surgical excision of TBA, as seen in one of our four operated cases. Mortality is reported to be high despite progress in treatment, while five of the six children treated by us responded well to the treatment.

Comparison of Postmortem Techniques for the Detection ofMycobacterium Bovisin White-Tailed Deer (Odocoileus Virginianus)

A retrospective study of various diagnostic postmortem techniques used in a 4-year surveillance program for detection of Mycobacterium bovis infection in wild white-tailed deer (Odocoileus virginianus) was conducted. The tests evaluated were routine histopathology, acid-fast staining, detection of acid-fast bacilli in culture, and an M. tuberculosis group-specific genetic probe applied to pure cultures. Each of these techniques were compared with a reference or "gold standard" of mycobacterial culture and identification. Histopathology, the most rapid form of testing for M. bovis infection in white-tailed deer samples, had a sensitivity of 98% and a specificity of 87%, resulting in a positive predictive value of 94%. The detection of acid-fast bacilli by staining was less sensitive than histopathology (90%), but its higher specificity (97%) resulted in a positive predictive value of 99%. The detection of acid-fast bacilli on culture was both highly specific (93%) and sensitive (100%). The group-specific genetic probe had the highest sensitivity and specificity and produced results in complete agreement with those of mycobacterial culture, suggesting that this technique could be used as the new "gold standard" for this particular wildlife tuberculosis surveillance program.