Fungal and mycobacterial cultures should not be routinely obtained for diagnostic work-up of patients with suspected periprosthetic joint infections.

AIMS: Fungal and mycobacterial periprosthetic joint infections (PJI) are rare events. Clinicians are wary of missing these diagnoses, often leading to the routine ordering of fungal and mycobacterial cultures on periprosthetic specimens. Our goal was to examine the utility of these cultures and explore a modern bacterial culture technique using bacterial blood culture bottles (BCBs) as an alternative. METHODS: We performed a retrospective review of patients diagnosed with hip or knee PJI between 1 January 2010 and 31 December 2019, at the Mayo Clinic in Rochester, Minnesota, USA. We included patients aged 18 years or older who had fungal, mycobacterial, or both cultures performed together with bacterial cultures. Cases with positive fungal or mycobacterial cultures were reviewed using the electronic medical record to classify the microbiological findings as representing true infection or not. RESULTS: There were 2,067 episodes of PJI diagnosed within the study period. A total of 3,629 fungal cultures and 2,923 mycobacterial cultures were performed, with at least one of these performed in 56% of episodes (n = 1,157). Test positivity rates of fungal and mycobacterial cultures were 5% (n = 179) and 1.2% (n = 34), respectively. After a comprehensive review, there were 40 true fungal and eight true mycobacterial PJIs. BCB were 90% sensitive in diagnosing true fungal PJI and 100% sensitive in detecting rapidly growing mycobacteria (RGM). Fungal stains were performed in 27 true fungal PJI but were only positive in four episodes (14.8% sensitivity). None of the mycobacterial stains was positive. CONCLUSION: Routine fungal and mycobacterial stains and cultures should not be performed as they have little clinical utility in the diagnosis of PJI and are associated with significant costs. Candida species and RGM are readily recovered using BCB. More research is needed to predict rare non-Candida fungal and slowly growing mycobacterial PJI that warrant specialized cultures. Cite this article: Bone Joint J 2022;104-B(1):53-58.

Symptomatic central nervous system tuberculoma, a case report in the United States and literature review.

Intracranial tuberculoma is one of the rare central nervous system manifestations of Mycobacterium tuberculosis (MTB), seen in only 1% of tuberculosis patients. It can manifest as single or multiple lesions, most commonly located in the frontal and parietal lobes. Clinical features are similar to any space-occupying lesion in the brain and can present in the absence of MTB symptoms in other parts of the body. In this article, a 69-year-old immunocompetent man, with history of treated latent tuberculosis infection (LTBI) was reported. He presented with multiple joint arthralgias, weight loss, odd behavior, forgetfulness, intermittent fevers and syncope. Brain imaging revealed numerous enhancing intra-parenchymal lesions in cerebral and cerebellar hemispheres. Patient was successfully treated with anti-tuberculosis medications and corticosteroids, with clinical improvement on future follow ups. High clinical suspicion for tuberculoma as a differential diagnosis of any brain lesion, even in immunocompetent patients in low MTB prevalence countries, can result in early diagnosis and successful clinical outcomes.

How radiology can help pulmonary tuberculosis diagnosis: analysis of 49 patients.

PURPOSE: To identify the most frequent radiological findings of pulmonary tuberculosis using CT of the chest, to determine those with the highest degree of correlation, and, if possible, to identify the most suggestive radiological findings for acid-fast bacilli (AFB) positive disease. MATERIALS AND METHODS: The radiological and clinical data of 49 patients submitted to CT during diagnosis were retrospectively analysed. The association between findings was assessed using Fisher's exact test, while correlation at CT scan was evaluated with the Spearman analysis. RESULTS: Bronchiectasis/bronchioloectasis (89.8%), nodule(s) (81.6%), tree-in-bud (TIB), and consolidation (79.6% each) figured among the most common parenchymal findings. Lymphadenopathy (26.5%) was the most common nodal finding. TIB and cavity showed the highest correlation (r = 0.577), followed by TIB and bronchi(olo)ectasis (r = 0.498), TIB and consolidation (r = 0.497), nodule(s), and ground glass opacity (r = 0.488). High correlation was found in only the seven most frequent parenchymal findings. Consolidation, TIB, and cavity were useful to predict the AFB stain positivity. CONCLUSIONS: Our series confirms the extreme heterogeneity of pulmonary tuberculosis. It also proves there are couple of findings which can drive us to the right diagnosis. While a triad of findings predicts AFB positivity, we have not found any predictive sign of AFB negativity; consequently, all patients with suspected imaging and clinical findings for TB should be isolated.

How Reliable is Sputum PCR Test in the Diagnosis of Pulmonary Tuberculosis When Sputum Smear is Negative? / 결핵

BACKGROUND: Recent technological developments have introduced a new method to identifying M. tuberculosis complex DNA in clinical samples directly. The direct amplification test (DAT) is approved for identifying M. tuberculosis complex in respiratory specimens that are smear-positive for acid-fast bacilli (AFB). When there is a discrepancy between the AFB smear and DAT, no information on their clinical utility is currently available. In this study, the diagnostic reliability of DAT was investigated in suspected pulmonary tuberculosis patients whose sputum AFB smear was negative. METHODS: From June 1, 1998 through May 30, 1999, 909 patients with presumed active pulmonary tuberculosis were enrolled. A sputum AFB stain, culture, DAT and /or biopsy were performed. using the criteria of clinical tuberculosis or confirmed tuberculosis, the positive predictive value of DAT in diagnosing pulmonary tuberculosis was investigated. RESULTS: The positive predictive value of DAT was 82.1% by the clinically active tuberculosis criteria. However, it decreased to 61.5% when diagnosis was restricted to only to culture positive or biopsy proven cases. The false positive rate of DAT was 18.0%. CONCLUSION: The DAT is a valuable diagnostic method in suspected patients whose sputum AFB is was negative.

Evaluation of Enzyme Immunoassay for the Diagnosis of pulmonary Tuberculosis / 대한임상미생물학회지

BACKGROUND: The diagnosis of tuberculosis has been based on the detection of tubercle bacilli by acid-fast stain of smear or cultures, and recently the serologic diagnosis of tuberculosis has been provided a means of sensitive and specific detection of Mycobacterium tuberculosis. We evaluated the utility of enzyme immunoassay using determiner Tuberculosis Glicolipids(TBGL) antibody kit(Kyowa Medex Co. Ltd, Japan) to detect anti-TBGL antibody for diagnosis of pulmonary tuberculosis. METHODS: Anti-TBGL antibody assay was performed to the form 44 patients with active pulmonary tuberculosis(17 patients with smear positive, 7 patients with only culture positive, 20 patients with clinically active tuberculosis) and 80 controls (30 healthy controls, 24 patients with non-tuberculous respiratory diseases, 26 patients with inactive tuberculosis). We compared the sensitivity and specificity of anti-TBGL antibody with culture and AFB stain. RESULTS: Anti-TBGL antibodies were detected in 16 of 17(94%) smear positive patients, 4 of 7 patients with only culture positive and 16 of 20(80%) smear negative patients who had been clinically diagnosed as active pulmonary tuberculosis. Nine(35%) out of 26 patients with inactive tuberculosis, one(4%) out of 24 patients with non-tuberculous respiratory diseases and no one of healthy control had a positive antibody response. Overall sensitivity, specificity of the anti-TBGL antibody assay were 82%, 88%, respectively and sensitivities and specificities of culture and AFB smear 64%, 97%, and 49%, 100%, respectively. Anti-TBGL antibody titers in patients with active tuberculosis were significantly higher than control grup(P<0.05). Conclusions : The anti-TBGL antibody assay was sensitive, rapid and convenient. This assay will be useful as a tool for the diagnosis of tuberculosis in combination with other conventional methods.

Clinical Usefulness of Various Methods for the Diagnosis of Tuberculosis / 대한임상병리학회지

BACKGROUND: In the diagnosis of tuberculosis, methods that have high sensitivity and specificity such as polymerase chain reaction and serologic test of tuberculosis have been introduced recently. Thus, we performed AFB stain, culture, PCR-ybridization and serologic test of tuberculosis to determine the clinical usefulness of each method in patients who were diagnosed as having pulmonary and extrapulmonary tuberculosis. METHODS: With the study subjects of 72 patients (57 with pulmonary tuberculosis, 15 with extrapulmonary tuberculosis) and controls of 60 persons, we performed the AFB stain, culture, PCR-ybridization and serologic test using an ICT(R) tuberculosis kit (AMRAD, Australia). Then, we compared diagnostic results in each tests and the effect of multiple tests among various methods. RESULTS: In 57 pulmonary tuberculosis patients, 42 (73.7%) showed positive with AFB stain, 40 (70.2%) with culture, 53 (93.0%) with PCR-ybridization, 47 (82.5%) with serologic test. And in 15 extrapulmonary tuberculosis patients, 4 showed positive (26.7%) with AFB stain, 5 (33.3%) with culture, 7 (46.7%) with PCR-ybridization method, and 12 (80.0%) with serologic test. In 72 tuberculosis patients, 67 (93.1%) showed positive for any of more than 2 tests among the 4 testing methods; and among 3 testing methods combined in different ways, 53 (73.6%) to 60 (83.3%) showed positive of any of more than 2 tests. CONCLUSIONS: We think that using the traditional method of detecting bacteria together with PCR-ybridization or serologic test would be a fast and accurate method of diagnosing tuberculosis. Especially, in those cases with extrapulmonary tuberculosis or taking a specimen of sputum is difficult, we think that serologic test would help in the diagnosis.

Clinical Usefulness of Various Methods for the Diagnosis of Tuberculosis / 대한임상병리학회지

BACKGROUND: In the diagnosis of tuberculosis, methods that have high sensitivity and specificity such as polymerase chain reaction and serologic test of tuberculosis have been introduced recently. Thus, we performed AFB stain, culture, PCR-ybridization and serologic test of tuberculosis to determine the clinical usefulness of each method in patients who were diagnosed as having pulmonary and extrapulmonary tuberculosis. METHODS: With the study subjects of 72 patients (57 with pulmonary tuberculosis, 15 with extrapulmonary tuberculosis) and controls of 60 persons, we performed the AFB stain, culture, PCR-ybridization and serologic test using an ICT(R) tuberculosis kit (AMRAD, Australia). Then, we compared diagnostic results in each tests and the effect of multiple tests among various methods. RESULTS: In 57 pulmonary tuberculosis patients, 42 (73.7%) showed positive with AFB stain, 40 (70.2%) with culture, 53 (93.0%) with PCR-ybridization, 47 (82.5%) with serologic test. And in 15 extrapulmonary tuberculosis patients, 4 showed positive (26.7%) with AFB stain, 5 (33.3%) with culture, 7 (46.7%) with PCR-ybridization method, and 12 (80.0%) with serologic test. In 72 tuberculosis patients, 67 (93.1%) showed positive for any of more than 2 tests among the 4 testing methods; and among 3 testing methods combined in different ways, 53 (73.6%) to 60 (83.3%) showed positive of any of more than 2 tests. CONCLUSIONS: We think that using the traditional method of detecting bacteria together with PCR-ybridization or serologic test would be a fast and accurate method of diagnosing tuberculosis. Especially, in those cases with extrapulmonary tuberculosis or taking a specimen of sputum is difficult, we think that serologic test would help in the diagnosis.