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This report describes a black woman with a history of cutaneous Mycobacterium kansasii responsive to antituberculous drugs. A culture several years later of cutaneous lesions was also positive for Histoplasma capsulatum. Both cutaneous diseases are rare and most often occur in immunocompromised hosts. There is no known association between these two diseases. This patient may have an as-yet unidentified immunodeficiency that predisposes her to these rare infections. Her case emphasizes the importance of repeat biopsy for atypical skin lesions.
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PMID:Cutaneous Histoplasma capsulatum in a nonimmunocompromised patient with previously treated cutaneous Mycobacterium kansasii. 189 84

Diseases consequent to infection with mycobacterial organisms, such as Mycobacterium tuberculosis and other mycobacterial species, remain a significant health problem in the United States. Over the past decade several new factors have amplified this problem, the most significant of which is the ongoing epidemic of infection with the human immunodeficiency virus. This review will discuss the changing epidemiology of mycobacterial disease and emphasize the significance of these changes to the radiologist.
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PMID:The changing epidemiology of tuberculosis and other mycobacterial infections in the United States: implications for the radiologist. 189 96

In the United States, the decades preceding the 1980s were characterized by a decline in the incidence of tuberculosis. More recently, the trend has undergone a significant reversal: Case rates have been increasing by 3% to 6% annually. In 1990, more than 25,700 cases were reported to the Centers for Disease Control. In a sense, tuberculosis is adapting to the '90s. The recent increase in its incidence tends to affect populations with identifiable characteristics. Among the most important of these groups are the populations at high risk for infection by the human immunodeficiency virus. The increase is also fueled by cases in populations that are medically underserved, including foreign-born persons from high-prevalence countries, persons with low incomes, and persons living in long-term-care facilities--especially persons with previous tuberculosis infection. Thus, factors such as homelessness, chronic alcohol or drug abuse, malnutrition, and crowded living conditions continue to favor development and transmission of disease. The increase in the incidence of tuberculosis appears to be greatest when subpopulations in such circumstances are also at high risk for HIV infection. Complex issues in the diagnosis and treatment of tuberculosis arise from these epidemiologic patterns. HIV infection is associated with unusual presentations of tuberculosis. Thus, the clinician must maintain a high index of suspicion for the disease in the setting of HIV infection or risk of the infection. The populations at greatest risk are likely to be mistrustful of the medical system, making the long-term administration of potentially toxic chemotherapy more difficult than it already is. Chronic substance abuse may complicate compliance and add further difficulties to the monitoring of chemotherapy. At the same time, the monitoring becomes even more important in the physician's effort to minimize adverse effects of the medications. Outbreaks of drug-resistant disease have recently occurred, complicating the selection of drugs and affecting the duration of treatment. Despite all of these problems, it is essential to establish a diagnosis and initiate treatment rapidly, both to arrest the disease process and to limit its transmission. Since Mycobacterium tuberculosis is spread to uninfected persons in aerosols generated by coughing or sneezing, the infectiousness of a patient with active disease can be related, at least in part, to the number of organisms seen on sputum smears. Initiation of therapy is followed by a rapid decline in infectivity.
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PMID:Tuberculosis: a disease of the 1990s. 191 97

Increasing rates of human immunodeficiency virus (HIV) related tuberculosis have been noted and recently the clinical importance of the disease has been mentioned. The diagnosis of tuberculosis is more difficult in those patients with HIV seropositive than those with seronegative, because those with seropositive have atypical clinical features. A 29-year-old male, who was infected with HIV heterosexually in Central Africa in 1986, was admitted to our hospital with a history of general malaise and weight loss in April, 1989. Laboratory and physical examinations revealed anemia, thrombocytopenia, the elevation of LDH, and giant intraabdominal lymphadenopathies, suspecting malignant lymphoma. Mycobacterium was isolated from the sputa in April and was confirmed as M. tuberculosis using a DNA probe in May, 1989. Clinical symptoms including giant lymphadenopathies and laboratory abnormalities improved with antituberculosis therapy. Development of a rapid method for the diagnosis of tuberculosis was warranted in this case.
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PMID:[A case of human-immunodeficiency virus infection related Mycobacterium tuberculosis with atypical clinical features]. 191 20

The use of empiric therapy for immunocompromised hosts has been one of the major advances in the management of such patients. Such therapy has been put into practice primarily for patients with neutropenia induced by cytotoxic chemotherapy. The empiric antibiotic regimens include in their coverage the bowel, skin, and intravenous-catheter flora anticipated for patients in a particular hospital. Less often, physicians treat empirically for opportunistic infections that complicate defects in helper cells, although empiric therapy for presumed Pneumocystis carinii pneumonia and Toxoplasma gondii infection of the central nervous system has become commonplace for patients infected with human immunodeficiency virus. Physicians also should consider environmental factors that expose patients to certain opportunistic organisms. Examples of such pathogens include Mycobacterium tuberculosis and Histoplasma capsulatum. The particular microorganisms considered to be opportunistic vary in different parts of the world and in different hospitals, and their designation as such may change rapidly. Multiple environmental exposures and immune defects, rather than just one factor, may be responsible for opportunistic infections and should be investigated and taken into account when empiric therapy is planned. Preventive measures, including simply rigorous hygiene, should precede and may obviate the need for empiric therapy.
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PMID:Empiric therapy for the immunocompromised host. 192 22

For many years tuberculosis has been known to occur with greater frequency among persons with disorders that impair host defenses. In most instances these processes interfere with the immune response to Mycobacterium tuberculosis, whereas, in a few, such as silicosis, the probable abnormality is a nonimmune defect in macrophage function. Infection with the human immunodeficiency virus (HIV) causes progressive and ultimately profound depression of both humoral and cell-mediated immunity and, thus, is an extremely potent risk-factor for tuberculosis. Presumably the major effect of HIV infection that predisposes persons to developing tuberculosis is the reduction in circulating T-helper (CD4+) lymphocytes which causes a reduction in cytokine production and a consequent decrease in the functional capabilities of macrophages. However, a number of questions concerning pathogenesis of tuberculosis related to HIV remain. Available data suggest that the magnitude of the risk for developing tuberculosis among persons infected with both HIV and M. tuberculosis is very high, 8% in one prospective study. Because of the epidemic of HIV infection, the progressive downward trend in the incidence of tuberculosis in the United States has reversed and in 1989 there was a 5% increase in the number of cases. Preliminary data for 1990 suggest that there will be an 8 to 10% increase over 1989. Also in the United States approximately 3% of tuberculosis patients have been found to be HIV seropositive. The clinical features of tuberculosis in patients with HIV infection vary depending on the degree of immunosuppression. With mild immunosuppression early in the course of HIV infection tuberculosis presents in a "typical" way with positive tuberculin skin tests, upper lobe cavitary infiltrates on chest film and positive sputum smears and cultures. As the HIV infection progresses, the mode of presentation of tuberculosis becomes more "atypical" with negative skin tests, multiple sites of involvement, chest films showing diffuse noncavitary infiltrates often accompanied by intrathoracic lymphadenopathy. The key to diagnosis is maintaining a high index of suspicion for tuberculosis, especially in patients with advanced HIV disease and including appropriate laboratory examinations in the evaluations of such persons. Regardless of the stage of HIV infection the response to treatment for tuberculosis is generally favorable if it is begun promptly. Standard therapy utilizing isoniazid, rifampin, and pyrazinamide with or without ethambutol have been associated with high rates of cure. Relapse has been uncommon. There has been, however, at least one outbreak of tuberculosis caused by isoniazid and rifampin resistant organisms in which the response to therapy was very poor.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Clinical features, diagnoses, and management of tuberculosis in immunocompromised hosts. 194 27

For the purpose to establish the system to express foreign antigen from Mycobacterium bovis BCG. We have cloned, sequenced and expressed genes for secreting proteins, alpha antigen, MPB64, MPB57 and MPB70 from M. bovis BCG. The upstreams and structural genes were characterized. The gene for alpha antigen of Mycobacterium kansasii was also characterized. The gene for alpha antigen of M. kansasii (k-alpha) was chosen for the further study at first. This gene was fused with shuttle plasmid PIJ666-PAL5000 obtained from T. Kisser and transfected to M. bovis BCG (Tokyo). Transformant was obtained by a selection with kanamycin. It was able to secrete k-alpha antigen. DNA-containing a B-cell epitope (Glu-12-Leu-Asp-Arg-Trp-Glu-Lys-Ile-19) of human immunodeficiency virus type 1 P17 gag was fused to this vector at C terminal of k-alpha. Using this vector, we have succeeded to express foreign antigen in M. bovis BCG. The products were analyzed in one or two dimensional electro-phoresis. The results thus obtained will be reported elsewhere.
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PMID:[Study on recombinant BCG]. 194 33

To assess the influence of human immunodeficiency virus type 1 (HIV)-induced immunodeficiency on the clinical, radiographic, and pathologic features of disseminated tuberculosis (TB), we studied 79 patients presenting in 1984 through 1987 with miliary or focal disseminated disease due to Mycobacterium tuberculosis, as well as 4 additional non-HIV patients diagnosed after 1987. Clinically defined acquired immunodeficiency syndrome (AIDS) or AIDS-related complex (ARC) was present in 51 (Group 1). A total of 20 had TB unrelated to HIV disease (Group 2). The remaining 12 were excluded because the role of HIV could not be determined. Clinical features were similar between groups aside from younger age; lower hemoglobin, total leukocyte, lymphocyte, and platelet counts; and more frequent tuberculin anergy (90 versus 40%) in AIDS/ARC patients (p less than or equal to 0.03). Chest radiographs showed a miliary pattern in about half of each group. Pleural effusion occurred only in AIDS/ARC patients (24%, p = 0.02), but intrathoracic lymphadenopathy was present in about a third of each group. Tissue biopsies (n = 70) usually revealed necrotizing granulomatous inflammation in each group, with a tendency to greater necrosis and more numerous acid-fast bacilli in Group 1. Granulomas were usually poorly formed in AIDS/ARC patients (59 versus 18%, p = 0.01). Autopsy of 9 AIDS/ARC patients with overwhelming miliary TB revealed a "nonreactive" histologic pattern with poorly organized or absent granulomas, extensive necrosis, and numerous bacilli. HIV-related disseminated TB causes a major constitutional illness with a high short-term mortality (25%).(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Disseminated tuberculosis in the acquired immunodeficiency syndrome era. 195 49

Extrapulmonary infection with Pneumocystis carinii is an uncommon event in which the skin may be affected rarely. All cases heretofore described in immunocompromised hosts have involved the external auditory canal and mastoid areas. We describe two patients with acquired immunodeficiency syndrome and extrapulmonary cutaneous P carinii infection that involved the glabrous skin. The first was a 31-year-old white man seropositive for human immunodeficiency virus with prior episodes of P carinii pneumonia and infection with Mycobacterium avium-intracellulare evaluated for translucent papules on the skin with an appearance similar to molluscum contagiosum infection. Biopsy confirmed the diagnosis of cutaneous pneumocystosis. The second patient was a 36-year-old homosexual man with long-standing liver disease with a persistent cough, fever, and an abnormal chest roentgenogram. Cutaneous evaluation revealed a bluish macule on the sternal notch that on skin biopsy was diagnostic of cutaneous pneumocystosis. Treatment with intravenous pentamidine resulted in resolution of the pulmonary and cutaneous problems in both cases. Extrapulmonary P carinii infection may involve the skin at sites other than the external auditory canal and may have a nondescript appearance. Histologic findings are similar to those of pneumocystosis found elsewhere. Clinicians should be familiar with the nondescript nature of the eruption as skin biopsy may be helpful in establishing a diagnosis of systemic pneumocystosis.
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PMID:Cutaneous Pneumocystis carinii infection in patients with acquired immunodeficiency syndrome. 195 76

The experience with Mycobacterium kansasii infections in patients who are infected with human immunodeficiency virus (HIV) at Parkland Memorial Hospital in Dallas is presented, and the literature on such infections is reviewed. The absolute and relative paucity of reports of M. kansasii infections in HIV-positive patients is emphasized. M. kansasii infections in HIV-positive patients are classified as either pulmonary or disseminated. Evidence of the lack of therapeutic response in patients with disseminated infections and of the potential for therapeutic response in patients with infections limited to the lung is reviewed and documented. Other unresolved diagnostic and therapeutic issues concerning M. kansasii infections in HIV-positive patients are reviewed.
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PMID:Mycobacterium kansasii infections in patients positive for human immunodeficiency virus. 196 86


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