Life-threatening airway obstruction caused by penicilliosis in a leukemic patient

Clinical characteristics of HIV-associated tracheobronchial Talaromyces marneffei infection in seven patients in Guangxi, China

OBJECTIVES

Tracheobronchial Talaromyces marneffei (T. marneffei) infections among HIV-infected patients are rare. To improve understanding, we analyzed the clinical features, immune mechanisms, treatment, and prognosis of these patients.

METHODS

We collected clinical information from HIV-positive patients with talaromycosis admitted to the Fourth People's Hospital of Nanning from January 2015 to June 2022. Patients who presented with culture and/or histopathological proof of tracheobronchial T. marneffei infection were included.

RESULTS

A total of 108 patients with respiratory infections who underwent bronchoscopy were enrolled. Seven patients with tracheobronchial T. marneffei infection, all of whom were men with a median age of 48 years (range 39-50 years), were analyzed. Cough, sputum, fever, and weight loss were the most common symptoms. The total white blood cell count was normal or decreased, and all lymphocyte counts were decreased. All patients had reduced CD4+ T-cell counts, with values less than 50 cells/µL. The chest CT imaging signs included patchy signals or large areas of exudation, bronchial stenosis and occlusion. This was different from the lack of bronchial involvement. Endoscopically, the trachea and bronchial mucosa showed congestion, edema, surface attachment, nodules, lumen stenosis, obstruction, etc. T. marneffei spores were found via bronchial mucosal pathology in all 7 patients. Five patients were initially treated with intravenous infusion of amphotericin B for 2 weeks, followed by oral itraconazole capsules (200 mg) twice daily, and two patients were initially treated with itraconazole. Six patients were remission, and 1 died.

CONCLUSIONS

The clinical features of trachea invasion and nontracheal invasion are not unique, but chest CT reveals manifestations such as masses, solid shadows, and bronchial stenosis/obstruction. Bronchoscopy should be performed if possible, and the presence or absence of trachea T. marneffei infection should be confirmed. Antiviral therapy combined with antifungal therapy can improve patient prognosis.

Pulmonary Talaromycosis: A Window into the Immunopathogenesis of an Endemic Mycosis

Talaromycosis is an invasive mycosis caused by the thermally dimorphic saprophytic fungus Talaromyces marneffei (Tm) endemic in Asia. Like other endemic mycoses, talaromycosis occurs predominantly in immunocompromised and, to a lesser extent, immunocompetent hosts. The lungs are the primary portal of entry, and pulmonary manifestations provide a window into the immunopathogenesis of talaromycosis. Failure of alveolar macrophages to destroy Tm results in reticuloendothelial system dissemination and multi-organ disease. Primary or secondary immune defects that reduce CD4+ T cells, INF-γ, IL-12, and IL-17 functions, such as HIV infection, anti-interferon-γ autoantibodies, STAT-1 and STAT-3 mutations, and CD40 ligand deficiency, highlight the central roles of Th1 and Th17 effector cells in the control of Tm infection. Both upper and lower respiratory infections can manifest as localised or disseminated disease. Upper respiratory disease appears unique to talaromycosis, presenting with oropharyngeal lesions and obstructive tracheobronchial masses. Lower respiratory disease is protean, including alveolar consolidation, solitary or multiple nodules, mediastinal lymphadenopathy, cavitary disease, and pleural effusion. Structural lung disease such as chronic obstructive pulmonary disease is an emerging risk factor in immunocompetent hosts. Mortality, up to 55%, is driven by delayed or missed diagnosis. Rapid, non-culture-based diagnostics including antigen and PCR assays are shown to be superior to blood culture for diagnosis, but still require rigorous clinical validation and commercialisation. Our current understanding of acute pulmonary infections is limited by the lack of an antibody test. Such a tool is expected to unveil a larger disease burden and wider clinical spectrum of talaromycosis.

Airway obstruction caused by penicilliosis: a case report and review of the literature

Penicilliosis is an opportunistic infection in HIV-infected and other immunocompromised patients mostly in Southeast Asia, Southern China, Hong Kong, and Taiwan, with respiratory manifestations in about one-third of patients. We report the case of a 26-year-old non-HIV immunocompromised patient presenting with an airway obstruction caused by penicilliosis, together with a review of the literature of this rare condition.

Fatal pneumonia caused by Penicillium digitatum: a case report

Background

Penicillium species are among the most common fungi present in the environment and are usually considered non-pathogenic to humans. However, in immunocompromised hosts they can be virulent pathogens and can cause death. Penicillium digitatum is a plant pathogen that commonly causes a postharvest fungal disease of citrus called green mould; it very rarely causes systemic mycosis in humans. Here, we report a case of fatal pneumonia due to P. digitatum infection, as confirmed by repeated examination of cultured sputum.

Case presentation

A cavity was found in the left upper lung on routine chest X-ray in a 78-year-old undernourished male who had been diagnosed at age 66 with bronchial asthma and pulmonary emphysema. No increased sputum production was present. The presence of antigen-specific precipitating antibodies to Aspergillus flavus and P. digitatum was confirmed in the patient’s serum and also later pleural fluid by using Ouchterlony double immunodiffusion testing with A. flavus and P. digitatum antigens. The patient was treated over a period of months with itraconazole, micafungin, voriconazole, amphotericin B, and antibacterials. However, the cavity enlarged, the pleural effusion increased, and the patient began producing purulent sputum. He died from progressive renal failure. From sputum culture only one fungus was isolated repeatedly on potato-dextrose agar in large quantities. This fungus was confirmed to be P. digitatum by molecular identification. Partial sequences of the beta-tubulin gene were determined by using the primers Bt2a and Bt2b for PCR amplification and sequencing and underwent a BLAST search at the National Centre for Biotechnology Information, these results confirmed that the isolated fungus was P. digitatum.

Conclusion

To our knowledge, this is the first report of pulmonary infection with P. digitatum. Our patient had pulmonary emphysema and was elderly, and undernourished. These factors might have facilitated the infection. In his case, antimycotics were ineffective in treating the lung involvement. Although human infection with P. digitatum is considered rare, it appears that this organism can be very virulent and resistant to antimycotics.