A case report of disseminated Mycobacterium colombiense infection in an HIV patient

Coinfection of Cytomegalovirus, Pneumocystis jirovecii pneumonia, COVID-19, and Mycobacterium colombiense in an AIDS patient: A case report

We present an AIDS patient coinfected with Cytomegalovirus, Pneumocystis jirovecii pneumonia, nontuberculous mycobacteria, and COVID-19, who finally recovered from the coinfection. The 36-year-old man had two hospitalizations. In the first hospitalization, the patient was diagnosed with Cytomegalovirus, Pneumocystis jirovecii pneumonia, HIV, and COVID-19 quickly and accurately, and the corresponding treatment worked well. The second hospitalization can be divided into four stages: (1) Persistent fever period; (2) Persistent fever and Pulmonary Progression; (3) ICU period; and (4) Pneumothorax period. During the second hospitalization, the diagnosis of Mycobacterium colombiense was hard because the NGS, acid-fast bacilli, and culture of vomit, sputum, and bronchoalveolar lavage fluid were all negative. Still, we detected acid-fast bacilli in the blood mycobacterium culture. In conclusion, we report a severe pneumonia AIDS patient coinfected with Cytomegalovirus, Pneumocystis jirovecii pneumonia, COVID-19, and Mycobacterium colombiense who finally recovered from the disease. Nontuberculous mycobacteria infection is common in HIV patients, but bronchoalveolar lavage fluid NGS cannot identify nontuberculous mycobacteria in our report. Traditional blood culture was useful in detecting acid-fast bacilli in our study and then detecting the pathogens with NGS. Combining traditional microbial culture and emerging rapid NGS methods is more conducive to clinical diagnosis and treatment.

Disseminated Mycobacterium colombiense infection mimicking malignancy: A case report

Mycobacterium colombiense, an infrequently reported non-tuberculous mycobacterium, is characterized by its slow-growing nature and capacity to simulate malignancies in clinical presentation. This report details a case of disseminated M. colombiense infection initially misidentified as cancer due to atypical symptoms, negative etiological tests, and imaging suggestive of a neoplastic disease. However, comprehensive diagnostic investigations, including a bone marrow biopsy and flow cytometry analysis, excluded malignancy as the diagnosis. The patient subsequently developed palpable masses, from which a definitive diagnosis was made using metagenomic Next-Generation Sequencing (mNGS) and culture of aspirate. A regimen of clarithromycin, ethambutol, rifampin, and amikacin was administered, leading to substantial improvement and resumption of activities at the eight-month follow-up. This case highlights the diagnostic challenges posed by the nonspecific clinical presentation of disseminated M. colombiense infection and the importance of rigorous investigation to avoid grave misdiagnosis and treatment delays.

Disseminated Mycobacterium avium Infection with Different Clinical Presentation in Two Human Immunodeficiency Virus-positive Patients

ABSTRACT

Microorganisms belonging to the Mycobacterium avium complex (MAC) are ubiquitous in the environment, but only a minority of infected persons develop disease. An underlying lung disease or immune deficiency is a prerequisite for clinical manifestation. However, disseminated MAC disease primarily manifests in people living with human immunodeficiency virus (HIV) in the severe immunodeficiency stage with a whole host of clinical symptoms. We present two cases of disseminated M. avium infection in people living with HIV in the stage of severe immunodeficiency. Both patients exhibited distinct disease progression, with the absence of pulmonary symptoms being a common characteristic. The first patient predominantly experienced high fever, accompanied by diarrhea and severe anemia. The normothermia in the second patient was incongruent with the presence of marked cachexia, severe abdominal pain, and magnetic resonance imaging evidence of abdominal lymph node involvement. The causative agent was isolated from both sputum and stools. The patients underwent treatment that comprised aminoglycoside, macrolide, ethambutol, and rifampicin. Although both patients achieved optimal viral suppression of HIV, the immunologic response to antiretroviral therapy was suboptimal. The first patient died in the setting of severe immunodeficiency due to the development of decompensated liver cirrhosis, while the second patient demonstrated a slight reverse course of the disease.

Mycobacterium colombiense Pneumonia in HIV-Infected Patients: Three Case Reports and a Literature Review

Background

Mycobacterium colombiense pneumonia in HIV-infected patients is relatively unusual but is associated with a high mortality rate, as well as high rates of misdiagnosis and delayed diagnosis. Clinical metagenome next-generation sequencing (mNGS) may have potential for its accurate and timely diagnosis.

Case Presentation

We retrospectively reviewed the medical records of three HIV-infected patients who presented with M. colombiense pneumonia in Zhejiang Province between January 2019 and December 2020. No specific clinical presentations or radiological manifestations were found in any of the patients. The detection of M. colombiense is 28-55 days earlier using mNGS on bronchoalveolar lavage fluid (BALF) compared to traditional culture methods. A combined treatment of rifabutin, clarithromycin, or azithromycin, and ethambutol did not provide timely relief of symptoms in these three patients. In the early stage of treatment, moxifloxacin and linezolid were used for several weeks. The average course of treatment for all three patients was close to 17 months.

Conclusion

We recommend early BALF mNGS for fast and accurate diagnosis of M. colombiense pneumonia in HIV-infected patients with low CD4 counts and long duration of symptoms. Further, moxifloxacin and linezolid may be beneficial in the early stage of treatment.

Application of mNGS in the study of pulmonary microbiome in pneumoconiosis complicated with pulmonary infection patients and exploration of potential biomarkers

Background

Pneumoconiosis patients have a high prevalence of pulmonary infections, which can complicate diagnosis and treatment. And there is no comprehensive study of the microbiome of patients with pneumoconiosis. The application of metagenomic next-generation sequencing (mNGS) fills the gap to some extent by analyzing the lung microbiota of pneumoconiosis population while achieving accurate diagnosis.

Methods

We retrospectively analyzed 44 patients with suspected pneumoconiosis complicated with pulmonary infection between Jan 2020 and Nov 2022. Bronchoalveolar lavage fluid (BALF) specimens from 44 patients were collected and tested using the mNGS technology.

Results

Among the lung microbiome of pneumoconiosis patients with complicated pulmonary infection (P group), the most frequently detected bacteria and fungi at the genus level were Streptococcus and Aspergillus, at the species level were Streptococcus pneumoniae and Aspergillus flavus, respectively, and the most frequently detected DNA virus was Human gammaherpesvirus 4. There was no significant difference in α diversity between the P group and the non-pneumoconiosis patients complicated with pulmonary infection group (Non-P group) in pulmonary flora, while P< 0.01 for β diversity analysis, and the differential species between the two groups were Mycobacterium colombiense and Fusobacterium nucleatum. In addition, we monitored a high distribution of Malassezia and Pneumocystis in the P group, while herpes virus was detected in the majority of samples.

Conclusions

Overall, we not only revealed a comprehensive lung microbiome profile of pneumoconiosis patients, but also compared the differences between their microbiome and that of non-pneumoconiosis complicated with pulmonary infection patients. This provides a good basis for a better understanding of the relationship between pneumoconiosis and microorganisms, and for the search of potential biomarkers.

Clinical features of rare disseminated Mycobacterium colombiense infection in nine patients who are HIV-negative in Guangxi, China

OBJECTIVES

Localized or disseminated infection caused by different nontuberculous mycobacteria (NTM) species has been increasingly reported in recent years, but reports of Mycobacterium colombiense infection are extremely rare. Herein, we analyzed the clinical features of patients with disseminated M. colombiense infection.

METHODS

Patients diagnosed with disseminated M. colombiense infection between February 4, 2016 and August 25, 2021 at the First Affiliated Hospital of Guangxi Medical University were retrospectively analyzed.

RESULTS

NTM infection was diagnosed in 248 HIV-negative patients. Of these, nine patients with disseminated M. colombiense infection were enrolled. Five of these patients were positive for anti-interferon-γ autoantibodies. The lung, lymph nodes, bones, and joints were the most commonly involved organs. Anemia, fever, lymphadenopathy, cough and expectoration, and ostealgia were the most common symptoms. The levels of white blood cells and neutrophils were increased in eight patients. M. colombiense was detected by both metagenomic next-generation sequencing (mNGS) and culture in four patients and only by mNGS in the remaining five patients. All patients received combination anti-NTM therapy; five underwent surgery. The condition of eight patients improved, and one died during the treatment.

CONCLUSION

Patients infected with M. colombiense can present as disseminated infections, easily involving multiple organs, such as the lung, lymph nodes, bone, and joints, with fever, lymphadenopathy, and increased white blood cell and neutrophil counts. mNGS plays a crucial role in the early diagnosis of M. colombiense infection. Once diagnosed, timely and effective anti-NTM therapy, combined with local surgery if necessary, can improve the prognosis of patients with this condition.

Mycobacterium colombiense and Mycobacterium avium Complex Causing Severe Pneumonia in a Patient with HIV Identified by a Novel Molecular-Based Method

Non-tuberculous mycobacteria are conditional pathogens that can cause many diseases, among which pulmonary infections are the most common (65–90%). Mycobacterium avium and Mycobacterium abscessus are non-tuberculous mycobacteria most often associated with lung diseases. Mass spectrometry diagnostic techniques were not effective in Mycobacterium avium complex infection. We report a case of Mycobacterium colombiense and Mycobacterium avium complex causing severe pneumonia in an adult with HIV. Our group developed a novel molecular-based method to identify Mycobacterium species. Novel techniques such as molecular cloning which we have described here can make up for the inability of matrix-assisted laser desorption ionization-time of flight mass spectrometry to distinguish the multiple microorganisms present, and may add to the diagnostic toolkit and increase the accuracy and rapidity of diagnosis in the future.

Evidence of an environmental reservoir for emergent Mycobacterium colombiense

Mycobacterium colombiense, which belongs to the M. avium complex, is reported to have been isolated from cases of disseminated infection in both immunocompromised and immunocompetent patients. During the isolation of protists from water samples in French Guyana, we co-isolated a flagellated green alga (Polytoma sp.) and a mycobacterium identified as M. colombiense.