Thoracic manifestations of tularaemia: a case series

BACKGROUND

Tularaemia is a zoonotic disease caused by Francisella tularensis, a highly virulent bacterium that affects humans and small wild animals. It is transmitted through direct contact with infected animals or indirectly through contaminated soil, water or arthropod bites (e.g. ticks). Primary thoracic manifestations of tularaemia are infrequent and, therefore, a diagnostic challenge for clinicians.

METHODS

We report six tularaemia cases with exclusively thoracic involvement diagnosed in a clinic for pulmonary diseases in Bavaria between 10/2020 and 02/2022.

RESULTS

All patients lived or were active in rural areas, four reported a recent tick bite. All patients presented with thoracic lymphadenopathy and pulmonary tumours or consolidations; all underwent bronchoscopy with EBUS-TBNA of lymph nodes, three lung biopsies as well. Five patients showed inflammatory changes in the endobronchial mucosa. The main histological findings were necrotic epithelioid granulomas with remarkable granulocyte infiltration. All cases were identified by positive serology, five by PCR (here identification of F.t. ssp. Holarctica) from biopsy as well. As first-line therapy, oral ciprofloxacin was given (5/6); in 2/6 cases, a combination of quinolone-rifampicin was given.

CONCLUSIONS

Pulmonary tularaemia may occur after tick bites and without extrathoracic manifestations. In patients who present with thoracic lymphadenopathy and pulmonary consolidations and who are exposed to increased outdoor activities, tularaemia should be included in the diagnostic pathway. Histologically, the presence of neutrophil-granulocyte infiltrations might help to distinguish tularaemia from other granulomatous infections, e.g. tuberculosis. The combination of quinolone-rifampicin rather than i.v. gentamicin reduced length of hospital stay in two patients.

Aspergillus-specific IgG antibodies for diagnosing chronic pulmonary aspergillosis compared to the reference standard

OBJECTIVES

To evaluate the performance of Aspergillus-specific IgG antibodies for diagnosing chronic pulmonary aspergillosis (CPA) by using a cohort of patients with histologically proven CPA as a reference standard.

METHODS

We collected Aspergillus-specific IgG antibody titres from patients with histologically proven CPA in collaboration with CPAnet study sites in Denmark, Germany, Belgium, India, Moldova, and Pakistan (N = 47). Additionally, sera from diseased and healthy controls were prospectively collected at the Medical Clinic of the Research Center, Borstel, Germany (n = 303). Aspergillus-specific IgG antibody titres were measured by the ImmunoCAP® assay (Phadia 100, Thermo Fisher Scientific, Uppsala, Sweden). An Aspergillus-specific IgG antibody titre ≥50 mgA/L was considered positive.

RESULTS

Using patients with histologically proven CPA as the reference standard, the ImmunoCAP® Aspergillus-specific IgG antibody test had a sensitivity and specificity of 85.1% (95% CI: 71.7-93.8%) and 83.6% (95% CI: 78.0-88.3%), respectively. Patients with histologically proven CPA had significantly higher Aspergillus-specific IgG antibody titre with a median of 83.45 mgA/L (interquartile range 38.9-115.5) than all other cohorts (p < 0.001). False-positive test results occurred in one-third of 79 healthy controls.

DISCUSSION

Our study results confirm a high sensitivity of the Aspergillus-specific IgG antibody test for the diagnosis of CPA when using patients with histologically proven CPA as a reference standard. However, positive test results should always match radiological findings as false-positive test results limit the interpretation of the test.

Prediction of anti-tuberculosis treatment duration based on a 22-gene transcriptomic model

BACKGROUND

The World Health Organization recommends standardised treatment durations for patients with tuberculosis (TB). We identified and validated a host-RNA signature as a biomarker for individualised therapy durations for patients with drug-susceptible (DS)- and multidrug-resistant (MDR)-TB.

METHODS

Adult patients with pulmonary TB were prospectively enrolled into five independent cohorts in Germany and Romania. Clinical and microbiological data and whole blood for RNA transcriptomic analysis were collected at pre-defined time points throughout therapy. Treatment outcomes were ascertained by TBnet criteria (6-month culture status/1-year follow-up). A whole-blood RNA therapy-end model was developed in a multistep process involving a machine-learning algorithm to identify hypothetical individual end-of-treatment time points.

RESULTS

50 patients with DS-TB and 30 patients with MDR-TB were recruited in the German identification cohorts (DS-GIC and MDR-GIC, respectively); 28 patients with DS-TB and 32 patients with MDR-TB in the German validation cohorts (DS-GVC and MDR-GVC, respectively); and 52 patients with MDR-TB in the Romanian validation cohort (MDR-RVC). A 22-gene RNA model (TB22) that defined cure-associated end-of-therapy time points was derived from the DS- and MDR-GIC data. The TB22 model was superior to other published signatures to accurately predict clinical outcomes for patients in the DS-GVC (area under the curve 0.94, 95% CI 0.9-0.98) and suggests that cure may be achieved with shorter treatment durations for TB patients in the MDR-GIC (mean reduction 218.0 days, 34.2%; p<0.001), the MDR-GVC (mean reduction 211.0 days, 32.9%; p<0.001) and the MDR-RVC (mean reduction of 161.0 days, 23.4%; p=0.001).

CONCLUSION

Biomarker-guided management may substantially shorten the duration of therapy for many patients with MDR-TB.

Tuberkulose - Wann daran denken, wie diagnostizieren?

Obwohl die Tuberkulose mithilfe von Antibiotika gut heilbar ist und die Zahlen in Deutschland wieder stetig rückläufig sind, stirbt rechnerisch alle 22 Sekunden auf der Welt ein Mensch an Tuberkulose, 95% davon in Entwicklungs- und Schwellenländern. Die WHO hat in ihrer End-Tuberkulose-Strategie das Ziel formuliert, im Vergleich zu 2015 die Zahl der Tuberkuloseerkrankungen pro 100.000 Einwohner bis 2035 weltweit um 90% und die Zahl der Todesfälle um 95% zu senken. Die Coronakrise hat hier zu großen Rückschritten geführt, fast zwei Drittel der Tuberkuloseprogramme weltweit sind unterbrochen worden. Damit ist in vielen Teilen der Welt die Erreichung dieser Ziele gefährdet und es wird sogar mit zunehmenden Fallzahlen in den nächsten Jahren gerechnet. Aber gerade die Tatsache, dass die Erkrankung bei uns seltener wird führt zu einer Zunahme der Dauer vom ersten Symptom bis zur Tuberkulosediagnose. Der vorliegende Artikel soll Ihnen eine Hilfestellung geben, wann die Tuberkulose in die Differenzialdiagnostik einzubeziehen ist und wie das Krankheitsbild diagnostiziert werden kann. Die Therapie, ihre häufigsten Nebenwirkungen und die Problematik resistenter Tuberkuloseformen werden ebenfalls kurz dargestellt.

Evaluation of Xpert MTB/RIF with microscopy and culture for the diagnosis of tuberculosis in a referral laboratory in Nepal

Sputum microscopy and Xpert MTB/RIF are the primary rapid diagnostic methods for tuberculosis (TB) in Nepal. Disagreements among Xpert, microscopy, and culture, for example, cases with Xpert positive and microscopy negative, were frequently observed in Nepal including in our reference laboratory. The objective of this study was to compare the effectiveness of Xpert with culture and microscopy for TB diagnosis in Nepal. A total of 125 TB suspected sputum samples were processed for Xpert, microscopy, and culture. The Xpert results when compared with culture showed 100% sensitivity and 97.4% specificity with an excellent agreement (kappa = 0.96), whereas microscopy showed the sensitivity and specificity of 43.2% and 98.7%, respectively, with a moderate agreement (kappa = 0.4). The sensitivity and specificity of microscopy, when compared with Xpert, were 43.5% and 100%, respectively. The majority of Xpert positive samples of a medium MTB detection and all samples of low and very low MTB detection were missed by microscopy. Our study showed that Xpert MTB/RIF is a reliable tool for the diagnosis and management of TB in Nepal. Because of its high cost and sustainability, alternative simple and rapid diagnostic methods with a similar efficiency would be helpful for TB control in Nepal.

Clinical Evaluation of BD MAX MDR-TB Assay for Direct Detection of Mycobacterium tuberculosis Complex and Resistance Markers

BD MAX MDR-TB assay is a new molecular platform for the detection of Mycobacterium tuberculosis complex (MTBC) in clinical specimens and simultaneous detection of resistance toward isoniazid and rifampicin. This study assessed the assay's diagnostic accuracy by using pre-characterized MTBC culture-negative (n = 257), smear-negative/MTBC culture-positive (n = 93), and smear-positive/MTBC culture-positive (n = 153) respiratory specimens. Compared with culture, the overall sensitivity and specificity of BD MAX MDR-TB were 86.6% and 100%, respectively; sensitivities for smear-positive and smear-negative samples were 100% and 64.5%. Sensitivity and specificity for isoniazid and rifampicin resistance were 58.3% (biased low due to sample collection strategy in low prevalence setting), 99.3%, 100%, and 98.2%, compared with phenotypic drug resistance testing and 100%, 99.4%, 100%, and 99.4%, compared with GenoType MTBDRplus. In conclusion, BD MAX MDR-TB is an accurate assay for the diagnostic detection of MTBC in respiratory samples and its resistance toward the most important anti-TB drugs isoniazid and rifampicin. Due to its medium to high throughput, good validity, and ease of use, the assay will be of great benefit for medium-sized to large TB diagnostic centers.

Clinical Management of Multidrug-Resistant Tuberculosis in 16 European Countries

RATIONALE

Multidrug-resistant tuberculosis (MDR-TB) is a major burden to public health in Europe. Reported treatment success rates are around 50% or less, and cure rates are even lower.

OBJECTIVES

To document the management and treatment outcome in patients with MDR-TB in Europe.

METHODS

We performed a prospective cohort study, analyzing management and treatment outcomes stratified by incidence of patients with MDR-TB in Europe. Treatment outcomes were compared by World Health Organization and alternative simplified definitions by the Tuberculosis Network European Trialsgroup (TBNET).

MEASUREMENTS AND MAIN RESULTS

A total of 380 patients with MDR-TB were recruited and followed up between 2010 and 2014 in 16 European countries. Patients in high-incidence countries compared with low-incidence countries were treated more frequently with standardized regimen (83.2% vs. 9.9%), had delayed treatment initiation (median, 111 vs. 28 d), developed more additional drug resistance (23% vs. 5.8%), and had increased mortality (9.4% vs. 1.9%). Only 20.1% of patients using pyrazinamide had proven susceptibility to the drug. Applying World Health Organization outcome definitions, frequency of cure (38.7% vs. 9.7%) was higher in high-incidence countries. Simplified outcome definitions that include 1 year of follow-up after the end of treatment showed similar frequency of relapse-free cure in low- (58.3%), intermediate- (55.8%), and high-incidence (57.1%) countries, but highest frequency of failure in high-incidence countries (24.1% vs. 14.6%).

CONCLUSIONS

Conventional standard MDR-TB treatment regimens resulted in a higher frequency of failure compared with individualized treatments. Overall, cure from MDR-TB is substantially more frequent than previously anticipated, and poorly reflected by World Health Organization outcome definitions.

Treatment responses in multidrug-resistant tuberculosis in Germany

BACKGROUND

Excellent treatment outcomes have recently been reported for patients with multi/extensively drug-resistant tuberculosis (M/XDR-TB) in settings where optimal resources for individualised therapy are available.

OBJECTIVE

To ascertain whether differences remain in treatment responses between patients with M/XDR-TB and those with non-M/XDR-TB.

METHOD

Patients with TB were prospectively enrolled between March 2013 and March 2016 at five hospitals in Germany. Treatment was conducted following current guidelines and individualised on the basis of drug susceptibility testing. Two-month and 6-month sputum smear and sputum culture conversion rates were assessed. A clinical and radiological score were used to assess response to anti-tuberculosis treatment.

RESULTS

Non-M/XDR-TB (n = 29) and M/XDR-TB (n = 46) patients showed similar rates of microbiological conversion: 2-month smear conversion rate, 90% vs. 78%; culture conversion rate, 67% vs. 61%; time to smear conversion, 19 days (IQR 10-32) vs. 31 days (IQR 14-56) (P = 0.066); time to culture conversion, 39 days (IQR 17-67) vs. 39 days (IQR 6-85) (P = 0.191). Both clinical and radiological scores decreased after the introduction of anti-tuberculosis treatment.

CONCLUSION

There were no significant differences in scores between the two groups until 6 months of treatment. Under optimal clinical conditions, with the availability of novel diagnostics and a wide range of therapeutic options for individualised treatment, patients with M/XDR-TB achieved 6-month culture conversion rates that were compatible with those in patients with non-M/XDR-TB.

Genetic diversity and distribution dynamics of multidrug-resistant Mycobacterium tuberculosis isolates in Nepal

Multidrug-resistant tuberculosis (MDR-TB) is an emerging public health problem in Nepal. Despite the implementation of a successful TB control program in Nepal, notifications of MDR-TB are increasing, yet the reasons are unknown. The objective of this study was to understand the genetic diversity and epidemiological characteristics of MDR-Mycobacterium tuberculosis (MTB) isolates in Nepal. We isolated and genotyped 498 MDR-MTB isolates collected from April 2009 to March 2013 and analyzed the patients' background information. Our results showed that the lineage 2 (Beijing family) was the most predominant lineage (n = 241; 48.4%), followed by lineage 3 (n = 153, 30.7%). Lineage 4 was the third most prevalent (n = 73, 14.5%) followed by lineage 1 (n = 32, 6.4%). The lineages were significantly associated with geographic region, ethnic group, age and sex of patients. The Beijing genotype was found to have an important role in transmitting MDR-TB in Nepal and was significantly associated with the eastern region, mongoloid ethnic group and younger age group. We conclude that early diagnosis and treatment including molecular-epidemiological surveillance of MDR-TB cases will help to control transmission of MDR-TB in Nepal.

Evaluation of OMNIgene®•SPUTUM-stabilised sputum for long-term transport and Xpert® MTB/RIF testing in Nepal

SETTING

German Nepal TB Project, National Tuberculosis Reference Laboratory, Kathmandu, Nepal.

OBJECTIVE

To evaluate whether transporting samples in OMNIgene®•SPUTUM (OM-S) reagent from a peripheral collection site to a central laboratory in Nepal can improve tuberculosis (TB) detection and increase the sensitivity of Xpert® MTB/RIF testing.

DESIGN

One hundred sputum samples were split manually. Each portion was assigned to the OM-S group (OM-S added at collection, airline-couriered without cold chain, no other processing required) or the standard-of-care (SOC) group (samples airline-couriered on ice, sodium hydroxide + N-acetyl-L-cysteine processing required at the laboratory). Smear microscopy and Xpert testing were performed.

RESULTS

Transport time was 2-13 days. Overall smear results were comparable (respectively 58% and 56% smear-negative results in the OM-S and SOC groups). The rate of smear-positive, Mycobacterium tuberculosis-positive (MTB+) sample detection was identical for both treatment groups, at 95%. More smear-negative MTB+ samples were detected in the OM-S group (17% vs. 13%, P = 0.0655).

CONCLUSION

Sputum samples treated with OM-S can undergo multiday ambient-temperature transport and yield comparable smear and Xpert results to those of SOC samples. Further investigation with larger sample sizes is required to assess whether treating sputum samples with OM-S could increase the sensitivity of Xpert testing in smear-negative samples.

[Endobronchial Ultrasound Guided Needle Aspiration of a Lung Cyst and Eosinophilic Pneumonia]

We report the case of a young male patient with a solitary pulmonary echinococcus cyst. The diagnosis of Cystic Echinococcosis is based on clinical findings, imaging and serology. In the setting of lung cysts the diagnosis can be difficult, particularly as the sensitivity of the serologic tests is lower compared to liver cysts. Bronchoscopic ultrasound of the cystic lesion and respectively the analysis of the cyst aspirate can lead to the diagnosis. In the present case an eosinophilic pneumonia as the result of the puncture has to be discussed.

[Diffuse Pulmonary Ossification]

Diffuse pulmonary ossification (DPO) represents an uncommon condition usually associated with different underlying pulmonary and extrapulmonary diseases. In this work, we discuss eleven patients of our clinic with the diagnosis of a diffuse pulmonary ossification. We focus on histological changes in the surrounding lung tissue. Clinical and radiological findings were analysed. The aim of the study is to collect data for a better understanding of this condition, especially in association with interstitial lung disease.Three patients with interstitial lung disease had histological findings of UIP. The follow-up data of these patients showed a benign course of the disease.The analysis of the clinical data yielded a very heterogenous group. Regarding these fact we assume, that DPO is not an own entity, but a pathological epiphenomenon in the context of different conditions, possibly with pathogenetic overlap.

Multidrug-resistant tuberculosis in Europe, 2010-2011

Drug-resistant Mycobacterium tuberculosis is challenging elimination of tuberculosis (TB). We evaluated risk factors for TB and levels of second-line drug resistance in M. tuberculosis in patients in Europe with multidrug-resistant (MDR) TB. A total of 380 patients with MDR TB and 376 patients with non-MDR TB were enrolled at 23 centers in 16 countries in Europe during 2010-2011. A total of 52.4% of MDR TB patients had never been treated for TB, which suggests primary transmission of MDR M. tuberculosis. At initiation of treatment for MDR TB, 59.7% of M. tuberculosis strains tested were resistant to pyrazinamide, 51.1% were resistant to ≥1 second-line drug, 26.6% were resistant to second-line injectable drugs, 17.6% were resistant to fluoroquinolones, and 6.8% were extensively drug resistant. Previous treatment for TB was the strongest risk factor for MDR TB. High levels of primary transmission and advanced resistance to second-line drugs characterize MDR TB cases in Europe.

D-Dimer in the Early Diagnosis of Acute Mesenteric Ischemia Secondary to Arterial Occlusion in Rats

BACKGROUND

Early diagnosis of mesenteric ischemia can be life saving. The aim of this study is to investigate the time-dependent diagnostic value of plasma D-dimer and other ancillary laboratory evaluations such as creatine phosphokinase, lactic dehydrogenase, aspartate aminotransferase, alanine aminotransferase, amylase, and leukocyte count in an experimental superior mesenteric arterial occlusion (SMA-O) model in rats.

METHODS

Forty male Wistar-Albino rats were separated into 4 groups: 2-, 4-, 6-, and 12-hour SMA-O groups. After laparotomy, the SMA was identified and ligated for 2, 4, 6 and 12 h in the 4 respective study groups. Blood samples were taken for laboratory tests 2 h after laparotomy in the control group and at the end of the ischemic period in the study groups.

RESULTS

The longer the duration of mesenteric ischemia, the higher were the serum D-dimer levels in the study groups, and statistical significance was obtained at 2 h (p = 0.021). Sensitivity, positive predictive value, negative predictive value, and accuracy of the relation were 88.8, 88.8, 100 and 90%, respectively. Leukocyte count was significantly higher than controls after 12 h. No other laboratory parameter correlated positively with the duration of mesenteric ischemia.

CONCLUSION

Serum D-dimer measurements may be a valuable diagnostic parameter in the early diagnosis of mesenteric ischemia.

Does rofecoxib increase TNF-alpha levels?

OBJECTIVE

Rofecoxib (Vioxx), the first COX-2 selective non-steroidal anti-inflammatory drug (NSAID), was recently withdrawn from the market due to the increased risk of acute myocardial infarction. The precise mechanism responsible for this phenomenon still remains unknown. Tumor necrosis factor alpha (TNF-alpha) is a cytokine, possibly most responsible for mortality in patients with acute myocardial infarction. However, this study was designed to study possible effects of rofecoxib on the level of TNF-alpha by using MSU crystal induced inflammation in the rat subcutaneous air pouch model.

METHODS

Rat subcutaneous air pouches were produced and examinations commenced 6 days later. Control groups received only MSU crystals, or no crystals or drugs. To begin with, rofecoxib (30 mg/kg), indomethacin (20 mg/kg) or diclofenac (3 mg/kg) were administered to groups of 5 rats each. Thirty minutes later, MSU crystals were injected into air pouches, except for the negative control group. Twenty-four hours later, the rats were sacrificed for aspiration of fluid and for the dissection of pouch walls to determine leukocyte counts, pouch wall histology, and to assay IL-10 and TNF-alpha.

RESULTS

Intra-pouch injection of MSU crystals, compared to non-injected pouches, caused an increase in white blood cell count (WBC) (30 +/- 44.7 versus 4508 +/- 792.3 cells/mm3), in the numbers of pouch wall vessels (vascular index) (4.8 +/- 0.3 versus 11.4 +/- 1.5 vessels/high-power field) and in TNF-alpha (50.0 +/- 13.4 versus 70.34 +/- 20.9 ng/mL), but not in interleukin-10 (IL-10) (60.6 +/- 63.0versus 61.48 +/- 7.1). WBC and vascular index were significantly reduced in all study groups compared to the control group (p < 0.05). Levels of TNF- in fluids were unexpectedly and significantly (p < 0.05) increased in all cases. The highest level of TNF-alpha was found in the rofecoxib group. In contrast to TNF-alpha, IL-10 levels were significantly (p < 0.05) decreased in all three drug groups. Indomethacin tended to suppress inflammation more effectively. However, there was no significant difference between the groups for IL-10 (p > 0.05).

CONCLUSION

All three NSAIDs exhibited anti-inflammatory activity against MSU crystal induced inflammation. The difference in anti-inflammatory effects of these three non-steroidal drugs is seen not only in the anti-inflammatory effect on MSU induced inflammation but also in the nature of the effects. Refocoxib tended to increase the TNF-alpha level. Whether increased TNF-alpha levels can help explain the side effect of COX-2 specific inhibitors still requires further studies.