Mycobacterial Disease: Epidemiology, Diagnosis, Treatment, and Prevention

Using Team-Based Learning to Train Student Pharmacists to Perform Tuberculin Skin Testing

Objective. To evaluate the effectiveness of a team-based learning (TBL) model in training students to properly administer and interpret a tuberculin skin test (TST) in a laboratory course. Method. Team-based learning was used to deliver TST training to all second-year student pharmacists (n=120) in a patient care laboratory course. A 10-item TST Learning Opinion Survey was developed and administered to assess student pharmacists' self-perceived achievement of the class learning objectives, opinions about TBL learning experience, and interest in making TST a part of future practice. Results. All 120 student pharmacists achieved competency standards during skills evaluation. One hundred thirteen out of 120 students completed the survey instrument. The majority of respondents either agreed or strongly agreed that TBL helped them meet the TST training learning objectives of: demonstrating administration proficiency; demonstrating interpretation competency; proper reporting and patient counseling with a positive test result; and identifying when a second TST was necessary. Additionally, a majority of respondents agreed or strongly agreed that the TBL model improved their knowledge of pre-laboratory material, aided their confidence in practicing TST placement, and improved their communication skills through peer work in a TBL environment. Conclusion. Through this innovative model, student pharmacists met the TST learning objectives and developed knowledge and confidence. This activity can be replicated at other colleges, expanding the development of student pharmacists who are confident in their ability to provide TST services.

Morbidity Trends and Risk of Tuberculosis: Mexico 2007-2017

Background

To know the current status of the epidemiological and geographic distribution of tuberculosis and its complication meningeal tuberculosis in Mexico, this work analyzes national surveillance data (ten years) issued by the General Directorate of Epidemiology (GDE).

Methods

An observational and retrospective analysis of monthly and annual reports of pulmonary and meningeal tuberculosis cases from January 2007 to December 2017 was performed on the annual reports issued by the GDE in Mexico. The number of cases and incidence were classified by year, state, age group, gender, and seasons.

Results

A national case distribution map of pulmonary and meningeal tuberculosis incidence was generated. During this period, a total of 184,003 and 3,388 cases were reported with a median of 16,727.5 and 308 cases per year for pulmonary and meningeal tuberculosis diseases, respectively. The number of cases and incidence of pulmonary and meningeal tuberculosis per year showed that male gender presented a continuous increase in both parameters. The geographic analysis of the distribution of cases of tuberculosis showed that states like Guerrero, Tabasco, and Veracruz presented higher means of tuberculosis cases during this period. Northern states had the highest number of cases in the country compared to other states. In Mexico, pulmonary tuberculosis and meningeal tuberculosis are seasonal. Interestingly, cases of meningeal tuberculosis show an increase during October and November (autumn).

Conclusions

In Mexico, during the years 2007-2017, there has been an increase in the proportion of male TB patients. It remains necessary to implement strategies to detect TB in the adult population, especially among men, because tuberculosis could be difficult to recognize in an early stage in the population, and the appearance of resistant strains can cause an increase in the incidence of the disease.

Matching AIDS and tuberculosis registry data to identify AIDS/tuberculosis comorbidity cases in California

The purpose of this study was to evaluate the sensitivity and positive predictive value (PPV) of a registry data linkage procedure used in the California AIDS and Tuberculosis (TB) Registry Data Linkage Study to identify AIDS/TB comorbidity cases in California. The California AIDS registry data from 1981 to 2006 were linked to the California TB registry data from 1996 to 2006 using LinkPlus, a probabilistic record linkage program developed by the Centers for Disease Control and Prevention, and matched results were manually reviewed to determine true or false matches. We estimated the sensitivity of this procedure to range from 98.0 per cent (95% confidence interval, CI: 97.3%, 98.7%) to 98.8 per cent (95% CI: 98.1%, 99.2%), and the PPV to be 100 per cent (95% CI: 96.8%, 100.0%). Our study demonstrated the feasibility of using this linkage procedure to match AIDS and TB registry data with a very high degree of accuracy.

The bacterial and host factors associated with extrapulmonary dissemination of Mycobacterium tuberculosis

With high morbidity and mortality worldwide, tuberculosis (TB) is still an important public health threat. The majority of human TB cases are caused by Mycobacterium tuberculosis. Although pulmonary TB is the most common presentation, M. tuberculosis can disseminate into other organs and causes extrapulmonary TB (EPTB). The dissemination of bacteria from the initial site of infection to other organs can lead to fatal diseases, such as miliary and meningeal TB. Thoroughly understanding the mechanisms and pathways of dissemination would develop therapies to prevent the lethal prognosis of EPTB (miliary and meningeal TB) and vaccines to promote the development of adaptive immunity. This review focuses on risk factors of EPTB, bacterial and host genes involved in EPTB, and potential mechanisms of M. tuberculosis extrapulmonary dissemination.

Prevalence of HIV-1 infection among patients with leprosy and pulmonary tuberculosis in a semi-arid region, Nigeria

Much evidence exists on pulmonary tuberculosis (PTB) as a presenting feature of HIV infection or AIDS-related complex, while few reports exist of a direct association between HIV infection and leprosy. This study was carried out to see whether or not an association between leprosy and HIV infection existed, similar to that of PTB in the region of Maiduguri, Nigeria. Of 105 patients with leprosy, 11(10.5%) were positive for HIV antibody. Of 58 patients with suspected PTB, 11(19%) were positive for HIV antibody. Twenty-seven (47%) of the 58 had active PTB, with results of sputum smear and culture positive for mycobacterium, and six of these (22.2%) were also positive for HIV antibody. Odds ratios (OR) obtained by conditional logistic regression (matched) analysis were 3.52 (95%, CI 1.03-12.07) and 2.53 (95%, CI 1.04-6.15) for association between HIV-1 and PTB and leprosy, respectively. HIV infection was more prevalent among leprosy patients aged under 30 years, OR = 4.25 (95%, CI 1.25-14.42). The prevalence of HIV-1 infection was at borderline significance, higher in PTB and leprosy patients than in blood donors, Fisher's exact test (two-tailed) p = 0.07 and p = 0.05, respectively.

Isolation, PCR based identification, and sensitivity pattern of environmental mycobacteria from leprosy and tuberculosis patients

We have isolated and identified the biotype of environmental mycobacteria from the expectorate of leprosy patients, their contacts, their drinking water supply and also from the sputa samples of tuberculosis patients. 78% of the isolates from lepromatous leprosy patients and their contacts wereMycobacterium fortuitum- chelonae complex (MFC), 9%Mycobacterium avium complex (MAC), 9%Mycobacterium scrofulaceum and 4% wereMycobacterium smegmatis. Among the isolates from tuberculosis patients 63% belonged toM. fortuitum- chelonae complex, 19% toM. avium complex, 12% toMycobacterium Kansasii and 6% toM. smegmatis. All the isolates were multi-drug resistant when tested for sensitivity total of 21 drugs. TheMycobacterium fortuitum-chelonae complex organisms from leprosy contacts were more sensitive to rifampicin than those isolated from lepromatous leprosy and tuberculosis patients. Among 23 isolates from leprosy patients one isolate was resistant to 20 drugs, one isolate to 17 drugs and another isolate was resistant to 13 drugs. Among the 18 isolates from drinking water supply six showed resistance to more than 12 drugs. Polymerase Chain Reaction (PCR) and subsequent hybridisation with specific probes confirmed all the isolated strains as nontuberculous mycobacteria (Using genus primers and probe sensitivity 100%) and none asM. tuberculosis, suggesting that PCR could be used to rapidly identify mycobacteria at the genus level and to rule out tuberculosis in leprosy patients at an early stage to decide on appropriate course of therapy.

Chest imaging in AIDS

A review of imaging in the acquired immune deficiency syndrome (AIDS) is presented. The imaging features can be conveniently categorized according to whether the presenting complications are infective (bacterial, protozoal, or fungal), bronchiectasis, neoplastic (Kaposi's sarcoma, AIDS-related lymphoma, or lymphoproliferative disease), or a miscellaneous group (non-specific interstitial pneumonitis, persistent generalized lymphadenopathy, or bronchogenic carcinoma).

Isolated cervical tuberculosis in patients with HIV infection

OBJECTIVE

Tuberculosis isolated to the head and neck region is common in patients with HIV infection. However, the management of isolated head and neck tuberculosis has not been reported in the literature. This study was done to describe the characteristics of tuberculosis isolated to the head and neck region in patients infected with HIV and to detect differences in presentation and diagnostic management based on the status of HIV infection at presentation.

METHODS

A retrospective study was performed including 38 patients infected with HIV who were seen with tuberculosis isolated to the head and neck region at two tertiary care centers during a 10-year period. These patients were divided into two groups on the basis of the HIV status at presentation, which indirectly reflects the level of immunosuppression. Group 1 included 11 patients (29%) with AIDS at presentation. Group 2 included 27 patients (71%) with HIV infection but not AIDS.

RESULTS

The cervical lymphatics were the most common site for isolated head and neck tuberculosis (89%), with the supraclavicular nodes most often involved (53%). Extralymphatic involvement was less common (11%), but involved a variety of anatomic locations (skin, spinal cord, larynx, parotid). The presenting history and physical examination had a low sensitivity for tuberculosis in patients with HIV infection, mainly because of the presence of multiple confounding factors. Purified protein derivative testing was highly sensitive for tuberculosis in patients with HIV infection alone (61 %); however, its usefulness was diminished in patients with AIDS (14%; p=0.03). Fine-needle aspiration biopsy was 94% sensitive for diagnosing tuberculosis and was not affected by the status of HIV infection. Surgical biopsy was the gold standard for diagnosing tuberculosis but was associated with chronically draining fistulas in a significant number of cases (14%).

CONCLUSIONS

These data suggest that tuberculosis should be considered in the differential diagnosis of all head and neck lesions in patients infected with HIV, even in the absence of pulmonary involvement. Purified protein derivative testing should be done liberally in these patients, with realization that the sensitivity of purified protein derivative testing is reduced in patients with AIDS. Fine-needle aspiration biopsy should be the key diagnostic test in this patient population, with open surgical biopsy reserved for highly suspicious cases in which other measures were not diagnostic.

Acquired drug resistance in Mycobacterium tuberculosis isolates recovered from compliant patients with human immunodeficiency virus-associated tuberculosis

We describe five compliant patients with human immunodeficiency virus (HIV)-associated tuberculosis (TB) that relapsed, with acquisition of resistance by the original Mycobacterium tuberculosis strains. Both the first and second isolates from each patient had the same IS (insertion sequence) 6110-based DNA fingerprint patterns. Three of the five patients developed TB that was resistant to rifampin alone; no mutation in the region of the rpoB gene was detected by a line probe assay in two of the isolates from these patients. We discuss several factors presumably associated with acquired drug resistance in HIV-infected patients, including exogenous reinfection, drug interactions, malabsorption of drugs, and the presence of a large organism burden.

The utility of a single sputum specimen in the diagnosis of tuberculosis. Comparison between HIV-infected and non-HIV-infected patients

STUDY OBJECTIVES

(1) To assess the utility of a single sputum specimen in the evaluation of HIV-infected patients who are suspected of having tuberculosis (TB). (2) To identify radiographic findings that discriminate between HIV-infected patients with TB and those with pneumonia of other causes.

DESIGN

Retrospective cohort analysis.

PATIENTS

All patients evaluated at Harborview Medical Center, Seattle, between January 1986 and July 1994 in whom culture of respiratory secretions grew Mycobacterium tuberculosis or Mycobacterium avium-complex. Patients who were coinfected with HIV formed the primary study group. Their chest radiographs were then compared with those of a matched group of patients with pneumonia of other causes.

MEASUREMENTS AND RESULTS

We identified 164 patients with TB, 20 of whom were HIV infected. The initial sputum specimen grew M tuberculosis in all HIV-infected patients and 99% of non-HIV-infected patients. Seventy percent of HIV-infected and 71% of non-HIV-infected patients had at least one positive smear. Most of these patients tested positive on their initial smear, and no significant difference was found between HIV-positive and HIV-negative patients (79% and 90%, respectively [p = 0.34]). The addition of a second sputum smear identified all HIV-infected patients and all but one in non-HIV-infected patients who were ultimately determined to be smear positive. A total of 27 HIV-infected patients had a positive acid-fast bacilli sputum smear during the study period, 14 of which were attributable to TB (specificity = 52%). The only radiographic findings that discriminated between HIV-infected patients with TB and those with pneumonia of other causes were the presence of cavitation or a miliary pattern (p = 0.014).

CONCLUSIONS

A single sputum specimen was sufficient to establish the diagnosis in all HIV-infected patients with pulmonary TB. A single negative sputum smear made the diagnosis of TB significantly less likely. However, a minimum of two smears were necessary to achieve an acceptable early diagnostic yield. The presenting chest radiograph failed to discriminate between HIV-infected patients with TB and pneumonia of other causes in most cases.

Tuberculosis. Part I

Tuberculosis has been a disease of human beings for thousands of years. In recent times it has waxed to become the feared White Plague of the eighteenth and nineteenth centuries and waned under the impact of effective chemotherapy until its elimination seemed possible by the early twenty-first century. The resurgence of tuberculosis in the past 10 to 15 years, caused by unanticipated events such as the appearance of the human immunodeficiency virus and deteriorating social conditions, also brought with it the problem of multiple drug resistance. Control measures such as tuberculin skin testing, perhaps somewhat forgotten when tuberculosis seemed to be a disease of the past, again became first-line defenses against spread of the disease. Environmental controls must be well understood and used effectively. Diagnosis of tuberculosis requires knowledge of the strengths and shortcomings of the various diagnostic methods and experience in their use. Practitioners are cautioned to remember that no diagnostic method, by itself, can be relied on to confirm or rule out tuberculosis. Well-tested diagnostic methods of chest radiograph, tuberculin skin testing, smear, and culture have been recently supplemented by rapid diagnostic tests based on amplification of bacterial RNA and DNA. More invasive diagnostic methods are sometimes required to diagnose extrapulmonary disease. Two-drug up to seven-drug therapy may be indicated for a case of tuberculosis, depending on evidence of the presence of multiple drug resistance. Duration of treatment can range from 6 to 12 months, also depending on identification of drug-sensitive or drug-resistant organisms. Failure of compliance can be a significant problem in patients who are homeless, or drug abusers, or who for various reasons cannot or will not complete a course of therapy. Directly observed therapy is strongly recommended for these patients, and for assistance in its administration the physician must cooperate with the local or state health department. The health department also must be notified whenever a case of tuberculosis is identified.

The changing face of tuberculosis

Tuberculosis (TB) remains an important public health problem worldwide, resulting in a estimated 8 to 10 million new cases and 2 to 3 million deaths each year. Between 1953 and 1985, the number of TB cases in the US declined by an average of 6% per year. However, since 1985, TB has been increasing in the US. Approximately 64,000 additional cases of the disease have been reported beyond the number expected had the rate of decline observed from 1980 to 1984 continued from 1985 through 1993. Increases in the number of TB cases have been significant in racial and ethnic minorities, in persons born outside the US, and in children less than 15 years of age. Infection with the human immunodeficiency virus (HIV) has also been recognized as a major risk factor for the development of active TB in persons with latent Mycobacterium tuberculosis infection. The unusual radiographic findings and the increased likelihood of extrapulmonary TB in HIV-infected persons make diagnosis of the disease problematic. Lastly, concomitant with the resurgence of TB has been the emergence of drug resistance. All of these factors make successful control of TB in the US difficult.

AIDS presenting as septic shock caused by Mycobacterium tuberculosis

Concurrent with the AIDS epidemic, an increasing incidence of tuberculosis has been noted. In HIV-infected patients with immunodeficiency, atypical forms of tuberculosis are seen. A case of disseminated tuberculosis with septic shock in an elderly patient with previously unknown HIV infection is reported.

The epidemiology of tuberculosis in Victoria

AIMS

To describe the epidemiology of Mycobacterium tuberculosis (MTb) in Victoria, Australia.

METHODS

We analysed data from the Victorian Mycobacterium Reference Laboratory database and MTb notifications to Health and Community Services Victoria, for the period 1948 to 1992.

RESULTS

The annual number of notified tuberculosis cases peaked at 1143 in 1954 and declined to 266 in 1992. The incidence rate decreased from 47 to 6.2 per 100,000 in the same period. The pattern of tuberculosis has changed significantly over the last two decades, reflecting the high prevalence of MTb in recent immigrants, particularly in those from South-East Asia. Among people born overseas the number of cases increased from 40% of notifications in 1970 to 80% in 1990; they are younger, more likely to be female and to have extrapulmonary disease, than their Australian-born counterparts. Between 1987 and 1991, the mean annual incidence of tuberculosis in people born in Australia and South-East Asia respectively was 1.5 and 47.5 per 100,000. People born in Vietnam, Cambodia and the Philippines had rates between 100 and 400 per 100,000. These rates have remained stable during the last six years. Almost 50% of migrant patients presented within five years, and 30% within two years, of arrival in Australia. The estimated mean annual incidence of MTb in homeless men between 1984 and June 1992 was 80 per 100,000. Resistance to all first-line drugs increased from 10.8% of all isolates in 1981 to 14.7% in 1990. The incidence of multi-drug resistant MTb (MDR-MTb) has been consistently less than 2% of isolates per year in the past 15 years. There were 14 cases of MTb and HIV between 1985 and June 1992. The mean annual incidence of MTb in people with AIDS is 1579 per 100,000 (range, 570-2420 per 100,000), with a relative risk of 236 (95% confidence interval [CI], 134-414). MDR-MTb has not been documented in HIV-infected individuals in Victoria.

CONCLUSION

Tuberculosis remains an important public health concern. Groups at high risk include people born overseas, the homeless, and people infected with HIV. Physicians caring for AIDS patients should consider the diagnosis of MTb, since its incidence in AIDS patients is so high. Our data suggest possible shortcomings in current methods of screening and prophylactic treatment of migrants and refugees. The rising rate of drug resistance cannot be ignored. We should consider strategies to ensure judicious use of anti-tuberculous drugs by physicians, and optimal patient compliance. These issues are critical to the future of tuberculosis control in Victoria.

Tuberculosis in infancy in the 1990s

In 1990, 25,701 cases of tuberculosis (TB) were reported in the United States, the largest annual increase since 1953. Children younger than 15 years of age accounted for 1596 new cases. The resurgence of TB can largely be contributed to the HIV epidemic. The clinical course, diagnosis, therapy, and prevention of TB in the perinatal period and in infancy are discussed in view of the epidemics of HIV and TB in the adult population.

HIV testing in patients with tuberculosis. Physician response to national recommendations

The epidemic of human immunodeficiency virus (HIV) disease has contributed to the resurgence of tuberculosis in the United States. For clinical and public health reasons, the Advisory Council for the Elimination of Tuberculosis has recommended that all patients with tuberculosis be tested for HIV antibodies. We reviewed the medical records of all patients with tuberculosis in whom a diagnosis was made at a Detroit medical center from July 1, 1986 to June 30, 1990, before and after recommendations were issued. Of 195 patients, 69 (35.4%) were tested for HIV antibodies: 73.7% of 57 patients whose medical records documented risk behaviors for HIV infection, and 19.6% of 138 patients who denied high-risk behaviors or whose medical records contained no risk information (relative risk of testing among patients with documented risk factors compared with others, 3.8; 95% confidence interval, 2.6 to 5.5). Testing of patients who denied risk behaviors or had no information in their records increased from 14.9% in the first 12 months to 30.4% in the last (p = 0.08, test for trend). In this population, national recommendations appear to have stimulated HIV testing, although most patients still are not being tested.

Disseminated nontuberculous mycobacterial infections in immunosuppressed patients

In summary, DNTM is an uncommon cause of infection in non-AIDS immunocompromised patients, but it is seen with increasing frequency as a late complication in AIDS patients who are severely debilitated. Non-AIDS patients may have pulmonary symptoms and parenchymal abnormalities on chest radiographs. These patients apparently may have clinically significant pulmonary infection. In contrast, AIDS patients with DNTM are unlikely to have clinically significant pulmonary disease. Although the lung is a common site of infection in these patients, they usually do not have pulmonary symptoms related to NTMB infection. Chest radiographs in these patients may show hilar or mediastinal adenopathy and/or pleural effusion. It is uncertain whether the parenchymal infiltrates noted in these patients are caused by NTMB or by coexisting processes. It is suspected that pulmonary NTMB in the AIDS patient is not likely to produce pulmonary parenchymal abnormalities on the chest radiograph.

The economic impact of tuberculosis in hospitals in New York City: a preliminary analysis

There is a nationwide resurgence of tuberculosis (TB) in the country’s urban centers; New York City stands at the forefront of this resurgence. The root causes are increased homelessness, drug addiction and poverty, all symbols of deteriorating social and economic conditions in the city. The inadequate level of public health resources devoted to TB has also contributed to its spread. Still, even with these factors, it is questionable whether the escalating number of TB cases in this country would have occurred without the reservoir of immunosuppressed persons, who are less resistant to the disease, created by the AIDS epidemic. The fear and urgency of this public health crisis, which has been emerging since the beginning of the last decade, are fueled by the rise of TB strains resistant to the first-line drugs and by the disease’s contagiousness.

Medical management of AIDS patients. Tuberculosis and nontuberculous mycobacterial disease

AIDS has been responsible for a significant increase in mycobacterial disease, which in this setting is often extrapulmonary. In contrast to HIV-associated Mycobacterium avium complex disease, HIV-associated tuberculosis is normally transmissible between humans by the aerosol route, occurs earlier than most AIDS-related infections, and is readily treatable and preventable with conventional drugs.

The impact of HIV on the usefulness of sputum smears for the diagnosis of tuberculosis

In a developing country, 289 patients were examined for active pulmonary mycobacterial disease (sputum smear and culture) and HIV infection (serology) to compare the sensitivity and positive predictive value of sputum smears for diagnosing pulmonary tuberculosis in patients with and without antibodies to HIV. Seventy-nine percent of HIV-seronegative vs 66% of HIV-seropositive patients with positive cultures for Mycobacterium tuberculosis were smear positive (P less than .05), and a positive sputum smear predicted the presence of M. tuberculosis in 90% of HIV seronegative vs 80% of HIV seropositive patients (P less than .05). In our opinion, HIV did not significantly compromise the diagnostic utility of the sputum smear.

Human exposure to rabies from pet wild raccoons in South Carolina and West Virginia, 1987 through 1988

During 1987 and 1988, exposures to eight pet wild raccoons in South Carolina and West Virginia resulted in administration of rabies post-exposure prophylaxis to 19 children and 26 adults. All eight raccoons appeared normal at the time of capture, and three had no signs of illness when sacrificed. The direct medical cost resulting from these exposures was $23,714 ($527 per person). Regulations and public education may help decrease this type of rabies exposure.

Mycobacterium gordonae: a possible opportunistic respiratory tract pathogen in patients with advanced human immunodeficiency virus, type 1 infection

STUDY OBJECTIVE

To determine if Mycobacterium gordonae is an opportunistic respiratory tract pathogen in patients infected with human immunodeficiency virus, type 1 (HIV-1).

DESIGN

Retrospective review of medical records of all patients with positive cultures for M gordonae from 1987 to 1989.

PATIENTS

Fifteen patients had positive sputum cultures for M gordonae: five patients had AIDS or had HIV-1 infections with less than or equal to 180 CD4 cells/cu mm, and ten patients had no clinical evidence of HIV-1 infection.

RESULTS

Three of the five HIV-1 infected patients had clinical, roentgenographic, and microbiologic evidence of pulmonary infection due to M gordonae that responded to antimycobacterial therapy. One of the two remaining HIV-1 infected patients had disseminated M tuberculosis and possible coinfection with M gordonae, and the other was lost to follow-up. None of the ten patients without evidence of HIV-1 infection was considered to have M gordonae respiratory tract infection.

CONCLUSIONS

Sputum isolates of M gordonae should be considered potential opportunistic respiratory tract pathogens in patients with advanced HIV-1 infection and with otherwise unexplained pulmonary infection.