沿海地区手部慢性特殊感染病因学及诊治研究

目的 探讨沿海地区手部慢性特殊感染的致病因素,以及与结核杆菌的关系,为临床早期正确诊治提供依据。方法对2002年6月至2004年4月收治的29例手部慢性特殊感染病例做组织病理学检查,直接抗酸染色,普通细菌培养,真菌培养,分枝杆菌培养,并对分离菌株进行生化分型。结果29例患者中细菌培养阳性12例。其中普通细菌培养阳性2例,其中1例为星形诺卡氏菌,另1例为表皮葡萄球菌;分枝杆菌培养阳性10例。直接抗酸染色检查2例阳性。结论手部慢性特殊感染患者应同时做常规细菌培养,真菌及分枝杆菌培养。非结核分枝杆菌感染尤其是海分枝杆菌远比结核菌常见,是沿海地区手部特殊感染的主要致病因素。     

Mycobacterial infection in HIV seropositive and seronegative populations, 1987-93.

BACKGROUND--Although the causes of the worldwide resurgence of tuberculosis are multifactorial, the HIV epidemic is believed to have had a central role. Control is further threatened by the emergence of multidrug-resistant tuberculosis. METHODS--A retrospective evaluation was undertaken of trends in pulmonary and extrapulmonary culture positive mycobacterial pathology, and the prevalence of drug-resistant tuberculosis in both HIV seropositive and, presumptively, HIV seronegative patients receiving their clinical care at St Mary's Hospital, London. Five hundred and thirty eight patients (188 of whom were known to be HIV seropositive) with positive mycobacterial isolates between January 1987 and March 1993 were identified from laboratory records. These were cross referenced with drug surveillance records. RESULTS--Overall, between 1987 and 1992 there was a progressive 3.5 fold increase in positive mycobacterial isolates and a 2.5 fold increase in patients with proven mycobacterial infection. This increase was greater within the HIV seropositive population. A total of 663 positive mycobacterial isolates was evaluated; the major pathogen identified was Mycobacterium tuberculosis (379 isolates, 57%). Three hundred and fourteen patients were diagnosed as having M tuberculosis, 49 of whom were HIV seropositive. M tuberculosis was predominantly isolated from the lung. Of 358 positive cultures for M tuberculosis (68 HIV seropositive, 290 presumptively HIV seronegative), only 27 isolates (7.6%), almost exclusively derived from presumed HIV seronegative patients, were resistant to either isoniazid, rifampicin, or both drugs together. No increases in drug-resistant isolates were observed over this period. CONCLUSIONS--There has been a considerable increase in the incidence of tuberculosis in both HIV seronegative and seropositive populations during the study period. The emergence of drug-resistant tuberculosis was not observed.     

Non-tuberculous pulmonary infections in Scotland: a cluster in Lothian?

BACKGROUND--A retrospective study was carried out to confirm the clinical impression that, in Lothian, non-tuberculous mycobacterial infections are as common as pulmonary tuberculosis. METHODS--All pulmonary isolates of Mycobacterium tuberculosis/bovis and non-tuberculous mycobacteria in Scotland from April 1990 to March 1993, and the notes of all patients with M malmoense isolates in Lothian, were reviewed. Information on mycobacterial culture procedures in Scottish laboratories was obtained as part of an audit project. RESULTS--Of all pulmonary isolates of mycobacteria in Lothian 53% (108/205) were non-tuberculous strains compared with 18% (140/800) for Scotland outside Lothian. Although comparable in population size and laboratory techniques, Lothian (108) had almost twice as many isolates of non-tuberculous mycobacteria as Glasgow (56), but the proportions of M malmoense and M avium intracellulare complex were similar in both areas. Of 41 patients with M malmoense isolates in Lothian 30 (75%) had clinically significant lung disease; only one was HIV positive. CONCLUSIONS--Non-tuberculous mycobacteria pose an increasing clinical problem in Scotland as a cause of pulmonary disease. There is a cluster of cases with M malmoense infection in Lothian which cannot be attributed to the high local prevalence of HIV.     

Mycobacterium tuberculosis and other mycobacteria

The immunocompromised post-transplant HIV-positive patient is at increased risk for mycobacterial infection. Early diagnosis and aggressive therapy is critical to successful outcome. Surgical therapy may be required in patients who have complex mycobacterial lung disease, drug resistant tuberculosis, or mycobacterial infections other than tuberculosis.     

Case Series and Review of the Literature of Mycobacterium chelonae Infections of the Lower Extremities

Mycobacterium chelonae infections involving the lower extremities are rare clinical entities that present a diagnostic challenge given its diverse clinical presentations ranging from superficial (e.g., cellulitis, painful vesicular lesions) to deep (e.g., tenosynovitis) infections. We present 1 cases of M chelonae infections of the feet diagnosed 6 to 12 months after initial symptoms representing the difficulty of diagnosing this condition. Both cases were successfully managed with aggressive surgical debridement and long durations of antibiotic therapy with long-term care. A comprehensive review of the literature of M chelonae infections of the lower extremities was performed to provide summary data on the presenting symptoms, examination findings, predisposing conditions, and management approaches of this rare, but emerging clinical entity. Our cases and comprehensive review serve to raise awareness of atypical mycobacterial infections, including M chelonae, and advocate for the early consideration of mycobacterial cultures in the diagnostic workup of chronic lower extremity infections especially in the setting of poor initial response to standard antibacterial therapies.     

Isolation of mycobacteria from patients seropositive for the human immunodeficiency virus (HIV) in south east England: 1984-92.

BACKGROUND--Tuberculosis and other mycobacterial infections are well recognised complications of HIV infection and surveillance is thus required. METHODS--All mycobacteria isolated from HIV positive subjects and referred to the Public Health Laboratory Service South East Regional Tuberculosis Centre (SERTC) from the first such case in 1984 until the end of 1992 were reviewed. RESULTS--A total of 803 mycobacteria isolated from 727 HIV positive subjects were referred to the SERTC during the study period. A single species was isolated from 660 patients: 150 members of the tuberculosis complex (146 M tuberculosis, two M bovis, and two M africanum), 356 M avium-intracellulare (MAI), and 154 other environmental mycobacteria. More than one mycobacterium was isolated from 67 patients. In 12 cases M tuberculosis and MAI were isolated from the same patient, almost always in that sequence, with an interval of 8-41 months between isolations. Most of the 407 isolates of MAI (74%) were considered to be clinically significant and often caused disseminated disease. In other cases single isolates of MAI were obtained from sputum or faeces and occasionally such isolates preceded disseminated disease by several months. Only 33 (14%) of the 229 isolates of environmental mycobacteria other than MAI were considered clinically significant. CONCLUSIONS--HIV related mycobacterial disease is increasing in incidence in south east England. Further studies are required to determine the significance of single isolates of MAI and other environmental mycobacteria as a guide to the need for preventive chemotherapy or immunotherapy.     

Tuberculous pleural effusions: increased culture yield with bedside inoculation of pleural fluid and poor diagnostic value of adenosine deaminase.

A prospective study of 111 adult patients with a pleural effusion was carried out in an area with a high prevalence of tuberculosis to compare the yield of bedside with laboratory inoculation of pleural fluid, and the yield and speed of a radiometric mycobacterial culture system (BACTEC) with that of conventional culture. The use of adenosine deaminase activity in pleural fluid as a diagnostic test for tuberculosis was also evaluated. In the 62 cases of tuberculosis confirmed histologically or by culture, or both, the BACTEC system had the same culture yield as conventional mycobacterial culture (positive in 14 cases-23%), but was significantly faster (18 versus 33 days). Bedside inoculation had a culture yield significantly higher than laboratory inoculation in the 24 patients tested (11 versus four). The remaining three diagnostic categories were malignant (28), miscellaneous (10), and undiagnosed (11). Median adenosine deaminase activity was significantly higher in tuberculous effusions than in any of the other categories, but there was considerable overlap between the groups. It is concluded that the BACTEC system is significantly faster than conventional mycobacterial culture and that bedside inoculation of pleural fluid substantially increases culture yield. Adenosine deaminase does not provide as valuable a diagnostic test of pleural tuberculosis as has been suggested.     

Mycobacterial infections in renal allograft recipients

Primary mycobacterial infections developed in five of 565 patients who had transplants during a 15-year period. All had negative PPDs and normal chest roentgenograms; none had tuberculosis before transplantation. Atypical mycobacteria were cultured in three of five infections. All were treated with a multiple-drug regimen, including isoniazid, rifampin, ethambutol, and streptomycin sulfate. In four of five patients, there were serious drug-related complications. No major initial alteration of immunosuppressive therapy was necessary in any of the patients. During the study, a treatment policy was followed that included one year of isoniazid treatment of all recipients with a positive PPD, history of tuberculosis, chest x-ray film suggestive of tuberculosis, or PPD-positive donor. An additional 14 transplant recipients were treated in accordance with this policy without complications or subsequent mycobacterial infections (32-month average follow-up). Despite the low incidence of mycobacterial infection in this series, the potential lethality and morbidity mandate constant vigilance.     

Identification of HIV patients with active pulmonary tuberculosis using urine based polymerase chain reaction assay

BACKGROUND: Despite the increased dissemination of tuberculosis among HIV infected patients, the diagnosis is difficult to establish. Traditional microbiological methods lack satisfactory sensitivity. We have developed a highly sensitive and specific nested polymerase chain reaction (PCR) capable of detecting Mycobacterium tuberculosis DNA in urine specimens and have used this test to examine urine specimens from HIV patients with active pulmonary tuberculosis. METHODS: Urine specimens from 13 HIV infected patients with microbiologically proven active pulmonary tuberculosis, 10 AIDS patients with non-tuberculous mycobacterial infection (documented by blood culture), 53 AIDS patients with no evidence of mycobacterial disease, and 80 healthy subjects (25 with positive skin test to purified protein derivative) were tested for M tuberculosis using PCR, acid fast staining (AFS), and culture. RESULTS: Of the urine specimens from patients with active tuberculosis, all tested positive by PCR, two by culture, and none by AFS. No reactivity was observed in urine specimens from patients with non-tuberculous mycobacterial infection. Of the 53 AIDS patients without mycobacterial infection, one had a positive urine PCR. Normal subjects were all negative. CONCLUSIONS: Urine based nested PCR for M tuberculosis may be a useful test for identifying HIV patients with pulmonary tuberculosis.     

Mycobacterial Infections in Rabbits: From the Wild to the Laboratory

Tuberculous mycobacterial diseases such as leprosy and tuberculosis are ancient diseases that currently continue threatening human health in some countries. Non‐tuberculous mycobacterial (NTM) infections cause a series of well‐defined pathological entities, as well as some opportunistic diseases that have also increased worldwide, being more common among immunocompromised patients but rising also in immunocompetent individuals. Reports on natural infections by mycobacteria in rabbits are scarce and mainly involve NTM such as Mycobacterium avium subsp. avium in pigmy rabbits in the United States and Mycobacterium avium subsp. paratuberculosis in wild rabbits in Europe. Rabbits have been used as laboratory animals through the years, both to generate immunological reagents and as infection models. Mycobacterial infection models have been developed in this animal species showing different susceptibility patterns to mycobacteria in laboratory conditions. The latent tuberculosis model and the cavitary tuberculosis model have been widely used to elucidate pathogenic mechanisms and to evaluate chemotherapy and vaccination strategies. Rabbits have also been used as bovine paratuberculosis infection models. This review aimed to gather both wildlife and experimental infection data on mycobacteriosis in rabbits to assess their role in the spread of these infections as well as their potential use in the experimental study of mycobacterial pathogenesis and treatment.     

Pulmonary Mycobacterium kansasii infection: comparison of the clinical features,treatment and outcome with pulmonary tuberculosis.

BACKGROUND: In the United Kingdom Mycobacterium kansasii is the most common pulmonary non-tuberculous mycobacteria to cause disease in the non-HIV positive population. METHODS: The clinical features, treatment, and outcome of 47 patients (13 women) of mean (SD) age 58 (17) years with culture positive pulmonary M kansasii infection were compared with those of 87 patients (23 women) of mean (SD) age 57 (16) years with culture positive pulmonary M tuberculosis infection by review of their clinical and laboratory records. Each patient with M kansasii infection was matched for age, sex, race and, where possible, year of diagnosis with two patients with M tuberculosis infection. RESULTS: All those with M kansasii infection were of white race. Haemoptysis was more common in patients infected with M kansasii but they were less likely to present as a result of an incidental chest radiograph or symptoms other than those due to mycobacterial infection. Patients with M kansasii were also less likely to have a history of diabetes, but the frequency of previous chest disease and tuberculosis was similar. An alcohol intake of > 14 units/week was less frequent in those with M kansasii, but there were no significant differences in drug history, past and present smoking habit, occupational exposures, social class, or marital status. Patients with M kansasii received a longer total course of antimycobacterial therapy and, in particular, extended treatment with ethambutol and rifampicin was given. There was no significant difference in outcome between pulmonary M kansasii or M tuberculosis infection. CONCLUSIONS: There are group differences between the clinical features of the two infections but, with the possible exception of diabetes and alcohol intake, these features are unlikely to be diagnostically helpful. Treatment of M kansasii infection with ethambutol, isoniazid, and rifampicin in these patients was as effective as standard regimens given to patients infected with M tuberculosis.     

Comparison of polymerase chain reaction amplification of two mycobacterial DNA sequences, IS6110 and the 65kDa antigen gene, in the diagnosis of tuberculosis.

BACKGROUND: Knowledge of the sequences of mycobacterial genes and the availability of DNA amplification techniques have raised the possibility that identification of mycobacterial DNA may offer a rapid and specific diagnostic test for tuberculosis. The correlation between the presence of Mycobacterium tuberculosis DNA and clinical tuberculosis, however, is not known. This study compared the results of polymerase chain reaction amplification of two M tuberculosis DNA sequences, IS6110 and the gene encoding the 65kDa heat shock protein (65kDa Ag), from sputum, bronchoscopy washings, and bronchoalveolar lavage fluid and related these findings to the presence of active and past tuberculosis. METHODS: Highly specific primers were used for amplification of IS6110 and 65kDa Ag DNA. Analysis was performed on one or more samples from 87 patients. RESULTS: IS6110 DNA was identified in samples from all six patients with active tuberculosis, from 15 to 18 patients with past tuberculosis, from five of nine contacts of patients with tuberculosis, and from nine of 54 patients with lung disease unrelated to tuberculosis. The 65kDa Ag DNA was identified in samples from all patients with active and past tuberculosis, from contacts of patients with tuberculosis, and from 14 of 42 patients with non-tuberculous lung diseases. CONCLUSION: These data suggest that the presence of IS6110 DNA correlates more closely with a tuberculosis related diagnosis than that of 65kDa Ag DNA and that both DNAs are found in most subjects with past tuberculosis or contacts of patients with tuberculosis. This may limit the clinical usefulness of these tests.     

Detection of mycobacterial DNA in pleural fluid from patients with tuberculous pleurisy by means of the polymerase chain reaction: comparison of two protocols.

BACKGROUND: The detection of mycobacterial DNA in clinical samples on the basis of the polymerase chain reaction is a promising approach for the rapid diagnosis of tuberculous infections. No consensus exists, however, about which protocols are most sensitive, and the usefulness of this approach in the diagnosis of tuberculous effusions has been assessed in few patients. METHODS: The sensitivity of two protocols was compared for the detection of DNA from Mycobacterium tuberculosis in samples containing known amounts of mycobacterial DNA and in DNA extracted from 15 tuberculous pleural effusions. The results obtained for pleural fluid have been compared with cytological findings and with results obtained by standard microbiological techniques. RESULTS: Mycobacteria could be detected by acid fast staining in none and by culture in three of the 15 pleural fluid samples. A protocol based on the detection of the IS6110 insertion element (which could detect one mycobacterial genome/sample reproducibly) gave a positive result in nine of the 15 tuberculous effusions, though some samples were only intermittently positive (p less than 0.05 compared with culture). In contrast, a protocol based on the detection of the gene coding for the 65 kD mycobacterial antigen (which could detect mycobacterial genomes only if there were at least 10/sample) gave a positive result in three of the 15 tuberculous effusions. Pleural fluid that was always positive with the amplification procedure detecting the IS6110 sequence contained more neutrophils (30% (SD 27%)) than samples that were intermittently positive or always negative (3% (3%)); mycobacterial DNA was never detected in the four samples containing less than 1% neutrophils. CONCLUSIONS: The amplification of the IS6110 insertion element represents a rapid and sensitive means of detecting M tuberculosis in tuberculous effusions. The enrichment of cells containing mycobacteria (possibly neutrophils) before DNA extraction may be required to improve the sensitivity of this approach.     

Disseminated tuberculosis after renal transplantation

Disseminated mycobacterial infections occurred in two female renal graft recipients late after transplantation. In the first patient, initially presenting with fever, diagnosis was made at autopsy. Temporary defervescence following antibiotic therapy with ofloxacin possibly contributed to the fatal diagnostic delay. In the second case, body temperature was normal throughout the protracted course of the patient's illness. Her presenting symptom was rapidly increasing ascites, attributed initially to chronic liver disease. These cases demonstrate that tuberculosis remains a serious complication after renal transplantation, in particular due to its sometimes atypical clinical manifestations. Response to antibacterial therapy has to be critically evaluated in order to avoid fatal diagnostic delay.     

Surgical management of resistant mycobacterial tuberculosis and other mycobacterial pulmonary infections

Between August 1983 and October 1990, 42 patients with resistant Mycobacterium tuberculosis underwent 44 pulmonary resections. During the same time, 38 patients with mycobacterial infections other than tuberculosis had 41 pulmonary resections. All patients either were poor candidates for medical therapy alone or had existing complications requiring surgical intervention. There was one operative death in each group, both from adult respiratory distress syndrome (postpneumonectomy pulmonary edema). Complications were high, with bronchopleural fistula most commonly occurring after right pneumonectomy in patients infected with Mycobacterium avium with superimposed infection with nonmycobacterial pathogens. In patients undergoing pneumonectomy for resistant Mycobacterium tuberculosis, the left lung was most often resected. It is recommended that if localized disease is present and medical treatment is likely to fail, pulmonary resection should be performed for resistant Mycobacterium tuberculosis infection after 3 months of drug-specific therapy. Muscle flaps were used frequently to avoid residual space and bronchial stump problems. Earlier resection in patients with indolent nontuberculous mycobacterial pulmonary infections is advocated before extensive polymicrobial contamination and right lung destruction.     

Disseminated tuberculosis after renal transplantation: A report of two cases

Abstract. Disseminated mycobacterial infections occurred in two female renal graft recipients late after transplantation. In the first patient, initially presenting with fever, diagnosis was made at autopsy. Temporary defervescence following antibiotic therapy with ofloxacin possibly contributed to the fatal diagnostic delay. In the second case, body temperature was normal throughout the protracted course of the patient's illness. Her presenting symptom was rapidly increasing ascites, attributed initially to chronic liver disease. These cases demonstrate that tuberculosis remains a serious complication after renal transplantation, in particular due to its sometimes atypical clinical manifestations. Response to antibacterial therapy has to be critically evaluated in order to avoid fatal diagnostic delay.     

Non-tuberculous and tuberculous mycobacterial peritonitis in peritoneal dialysis patients

Introduction: Peritoneal dialysis (pd)-associated mycobacterium peritonitis is an important clinical entity in patients with end stage renal disease. They present a significant diagnostic and therapeutic challenge for clinicians because clinical findings and laboratory investigations can not be differentiated from symptoms caused by non-tuberculous mycobacterium (ntm), Mycobacterium tuberculosis (tb) or other bacteria. The aim of the present article is to know the differences between the clinical manifestations and laboratory investigations, the appropriate diagnosis, treatment strategies and prognosis for tb and ntm disease in patients with pd-associated mycobacterial infections. Methods: This was a retrospective observational study conducted over a period of 25 years. Out of 1737 patients, only 7 were diagnosed with mycobacterial peritonitis. Result: Evaluable data showed that there were three patients diagnosed with ntm peritonitis and four patients with tuberculous peritonitis. The mean age of the patients was 53.9?±?11.8 years. Although all patients developed abdominal pain and cloudy dialysate, only four patients (57.1%) had fever. Two patients (28.6%) suffered severe sepsis and septic shock. Therefore, the patient survival rates for ntm and tuberculous peritonitis were 100.0% and 75.0%, respectively. Two patients were shifted to long-term hemodialysis; therefore, the technical survival rates for ntm and tuberculous peritonitis were 66.7% and 50.0%, respectively. Notably, recurrence of mycobacterial infection was found in one patient with both pulmonary tuberculosis and tuberculous peritonitis. Conclusion: The diagnosis of mycobacterial peritonitis remains a challenge to medical staffs because of its insidious nature, the variability of its presentation and the limitations of available diagnostic test.     

The surgical management of superficial infections caused by atypical mycobacteria

We have recently treated four patients with atypical mycobacterial skin infections. Two patients were infected with Mycobacterium smegmatis after self-injection with a veterinary-grade anabolic steroid. To our knowledge, this complication has not been previously described. The other patients had steroid-dependent asthma and lower extremity infections involving M. kansasii and M. chelonei after minor household trauma developed. Atypical mycobacterial skin infections may be seen as chronic ulcerations with violaceous edges, rolled margins, and significant subcutaneous necrosis. An indolent course and the clinical appearance may aid in diagnosis. In our experience, limited incision and drainage or dressing changes fail to eradicate these infections, even when accompanied by appropriate antibiotic therapy. Successful treatment requires aggressive debridement of all infected subcutaneous tissues and skin. Split-thickness skin grafting was successfully used to cover large wounds. Grafting did not appear to foster recurrent infection.     

Mycobacterium tuberculosis in the acquired immunodeficiency syndrome

Patients with human immunodeficiency virus (HIV) infection, with or without the diagnosis of acquired immunodeficiency syndrome (AIDS) or AIDS-related complex (ARC), have an increased incidence of tuberculosis, especially of an extrapulmonary nature. The condition is associated with significant morbidity and mortality. The reported incidence of the combination of tuberculosis and AIDS varies between 4% and 10% of AIDS patients, with a higher incidence noted in the male, inner-city, intravenous-drug-abuser population. Clinical findings may reflect the site of infection, but are often nondiagnostic. Diagnosis often requires biopsy for histopathologic evaluation and tissue culture to document the presence of granulomas and mycobacterial organisms. Universal body fluid precautions among these patients are mandatory, and respiratory isolation should be maintained during diagnostic evaluation and early treatment. These patients usually respond to standard antituberculosis therapy. Physicians should maintain a high index of suspicion of tuberculosis in patients with HIV infection. Conversely, the diagnosis of HIV infection should be considered in patients with unusual manifestations of tuberculosis. Because tuberculosis is one of the few potentially curable infections in the AIDS patient, recognition of its presence is crucial.