Renal Tuberculosis in the Modern Era

Elizabeth De Francesco Daher 0 1 2 Geraldo Bezerra da Silva Junior 0 1 2 Elvino Jose Guarda o Barros 0 1 2 0 Vicente Linhares 1198, CEP 60135-270 , Fortaleza, Ceara , Brazil 1 Department of Internal Medicine, Federal University of Ceara , Fortaleza, Ceara , Brazil; School of Medicine, Health Sciences Center, University of Fortaleza , Fortaleza, Ceara , Brazil; Department of Internal Medicine, School of Medicine, Federal University of Rio Grande do Sul , Porto Alegre, Rio Grande do Sul , Brazil 2 Authors' addresses: Elizabeth De Francesco Daher, Department of Internal Medicine, Federal University of Ceara , Fortaleza, Ceara , Brazil Tuberculosis (TB) is a disease caused by Mycobacterium tuberculosis. The disease remains as an important public health problem in developing countries. Extrapulmonary TB became more common with the advent of infection with human immunodeficiency virus and by the increase in the number of organ transplantation, which also leads to immunosuppression of thousand of persons. Urogenital TB represents 27% of extrapulmonary cases. Renal involvement in TB can be part of a disseminated infection or a localized genitourinary disease. Renal involvement by TB infection is underdiagnosed in most health care centers. Most patients with renal TB have sterile pyuria, which can be accompanied by microscopic hematuria. The diagnosis of urinary tract TB is based on the finding of pyuria in the absence of common bacterial infection. The first choice drugs include isoniazide, rifampicin, pirazinamide, ethambutol, and streptomycin. Awareness of renal TB is urgently needed by physicians for suspecting this disease in patients with unexplained urinary tract abnormalities, mainly in those with any immunosuppression and those coming from TB-endemic areas. - Tuberculosis (TB) is a disease that in most cases is caused by Mycobacterium tuberculosis; however, some cases can be caused by other Mycobacterium species in the M. tuberculosis complex.1 The disease became a serious public health problem in Europe during the industrial revolution, when the increases in population and population agglomeration in large cities were common; at that time, TB was responsible for more than 30% of all deaths.1 The incidence of TB is increasing, mainly in the developing world. According to the World Health Organization, approximately nine million new cases occur each year world wide.2 Most cases are in Asia (55%) and Africa (31%), followed by the eastern Mediterranean region (6%), Europe (5%), and the Americas (3%).2 Brazil is one of the 20 countries with the higher number of cases, and had 72,194 new cases in 2007, which corresponds to an incidence rate of 38 cases/100,000 persons.2 Extrapulmonary TB became more common with the advent of infection with human immunodeficiency virus (HIV) and the increase in organ transplantation, which results in in immunosuppression of organ recipients.3 Urogenital TB represents 27% of extrapulmonary TB cases, according to data from the United States, Canada, and England. It is the third most frequent form of extrapulmonary TB after pleural TB and lymphatic TB4 and occurs by hematologic dissemination of pulmonary TB in almost all cases. IMMUNOSUPPRESSION AND TUBERCULOSIS Development of immunosuppressive therapies is also responsible for the increase in the number of extrapulmonary TB cases. Patients who have undergone kidney transplantation, especially those who have used potent immunosuppressive drugs, are more susceptible to M. tuberculosis infection by reactivation of latent infections and primary infections.5 Matuck and others 6 showed that 4.5% (44 of 982) of renal transplant patients contracted TB. However, renal disease caused by Mycobacterium species is rare in immunocompetent persons.6 Mycobacterium spp. can be found in urine, water, and the environment but are not pathogenic. Treatment of patients with bladder cancer with Calmette-Gue rin bacillus (BCG) has also been reported as a cause of urogenital TB.7 TUBERCULOSIS AND HIV Persons infected with HIV have a 2037 times greater risk of TB than those who are not infected with HIV. In 2010, there were 8.8 million new cases of TB, of which 1.1 million were in patients infected with HIV.8 Tuberculosis is the most frequent opportunistic infection in patients infected with HIV and is also associated with significant mortality in this population.9 It is estimated that 10% of TB patients in the United States are infected with HIV.10 In a study with 532 HIV patients admitted to a tertiary hospital in our region, TB was present in 13% of patients, and severe forms of renal impairment were associated with increased mortality.11 Among the challenges of genitourinary TB are increasing drug resistance and co-infection with HIV.12 Infection with HIV increases the susceptibility for TB infection and disease progression. Tuberculosis can occur in any phase of HIV infection, ranging from asymptomatic to established acquired immunodeficiency syndrome.13 Infection with HIV is associated with a higher risk for extrapulmonary TB.10 In a recent study in Brazil with 66 patients with HIV and TB, extrapulmonary TB was observed in 31.8% of cases, of which 54% were ganglionar TB.13 Nourse and others14 in a study with 12 children with HIV and TB found a mean CD4 cell count of 508 cells/mL; four patients had nephrotic range proteinuria and hypoalbuminemia. Three of these patients had renal impairment. Renal biopsy specimens showed a severe interstitial inflammatory infiltrate and mild-to-moderate mesangial proliferation. An interstitial granuloma was seen in one patient. After treatment for TB, the proteinuria resolved and renal function improved. The authors concluded that TB contributes to proteinuric renal disease in HIV-infected children and that the renal disease improves after treatment for TB.14 TUBERCULOSIS-ASSOCIATED OBSTRUCTIVE KIDNEY INJURY Conte and others15 reported a woman who sought medical care because of dyspepsia. She had diabetes mellitus type 1 and retinopathy. She had a serum creatinine level of 1.2 mg/ dL, a glomerular filtration rate (GFR) of 69 mL/minute, proteinuria < 1 g/day, hematuria, and leukocyturia. There was a progressive increase in creatinine (2 mg/dL) and a decrease in the GFR (28 mL/minute). The urinary volume was 900 mL/ day and blood pressure was 130/80 mm Hg. Urinalysis showed 10 erythrocytes/high-power field, a pH 6.0, and a specific gravity 1,015. Pre-renal and renal causes of renal insufficiency were excluded. Investigation of post-renal kidney injury was conducted with ultrasound, pyelogram, and tomography. An increase in the size of the right kidney was found, with a reduction in renal parenchyma and moderate dilation of collecting system in the left kidney. After contrast infusion, it was not possible to see the right kidney. There were no calcifications. The right kidney was removed and histopathologic examination showed findings compatible with TB nephrop (...truncated)