Rapid on‐site evaluation facilitated the diagnosis of a rare case of Talaromyces marneffei infection

Abstract

transplant 11 years previously and at presentation was immunosuppressed with tacrolimus and mycophenolate mofetil. Her symptoms started whilst sailing in Crete, prior to which she had travelled extensively in southern China for 8 weeks in 2016. She is a lifelong nonsmoker and for the last several years has been sailing around the Mediterranean with frequent trips back to the UK. A computed tomography scan of the chest was performed in Greece which revealed a large left upper lobe (LUL) mass. A subsequent positron emission tomography/computed tomography in the UK showed a highly avid 10.4-cm left upper lobe necrotic mass with a very high fluorodeoxyglucose uptake, standardised uptake value max 21.4, suggestive of primary lung malignancy. There were also sub-centimetre station 5 and 6 nodes with high fluorodeoxyglucose uptake (standardised uptake value max up to 6.0), suspicious of involvement. Diagnostic EBUS-TBFNA and transoesophageal endoscopic ultrasound-guided (EUS) FNA were performed. Samples were obtained from station 11L lymph nodes via EBUS-TBFNA and the LUL mass via both EBUS-TBFNA and EUS-FNA. Detailed methods relating to specimen preparation were as described previously. 3 ROSE revealed no malignant cells from the station 11L node.Five aspirates from the LUL mass via EBUS-TBFNA were prepared as five air-dried Rapi-Diffâ stained direct spreads that at ROSE showed necrotic debris. Thereafter, a further five aspirates were performed by EUS-FNA, which revealed granulomatous inflammation. In light of these ROSE findings, an additional two aspirates were taken for microbiology assessment.Within the cytoplasm of both the single macrophages and the granulomas, numerous organisms were identified at ROSE on the air-dried slides ( Figure 1A) and subsequently on the SurePathâ slide ( Figure 1B). These microorganisms had both pale and dark staining poles. They stained positive with Grocott's methenamine silver staining, confirming their fungal nature ( Figure 1C) and were noted to be oval in shape with a transverse septum dividing the hyphae ( Figure 1D). Microbiological assessment revealed organisms with a typicalTaralomyces micromorphology with fungal hyphae undergoing conidiation at 30°C. In addition, culture of the sample on a Sabouraud agar slope at 30°C produced a red, diffusing pigment characteristic for T. marneffei ( Figure 1E,F).Clinically, T. marneffei infection is a challenging diagnosis. As demonstrated in this case, taralomycosis may be suspected in cytological specimens based on its characteristic morphology. The organisms are oval, spherical and sausage-shaped, 2-6 µm, display lighter and darker staining poles and have a central transverse septum, which stains densely with silver stain. 4,5 These features are similar to those of another intracellular pathogen, Histoplasma capsulatum, which is also a dimorphic fungus and an AIDS defining infection. The key differentiating features are the sizes of the organisms and the culture patterns.

Disseminated Talaromyces marneffei infection initially presenting as cutaneous and subcutaneous lesion in an HIV-Negative renal transplant recipient: a case report and literature review

“… 53/F England kidney coughing, green sputum MMF was discontinued; Tac dose was reduced Liposomal amphotericin B daily for 2 weeks; oral itraconazole twice daily for 6 months Cured Vergidis P. et al [ 38 ], 2021. Ma W, et al [ 39 ], 2018. 51/M Guang dong, China kidney serum creatinine elevation After admission: Tac and Methylpred were stopped; MMF was withheld; CsA (concentration ranging from 140.6 to 503.8 ng/mL) Liposomal amphotericin B (0.4 mg/kg/day); itraconazole (200 mg bid) Cured Peng J, et al [ 40 ], 2017.…”

Coinfection by Talaromyces marneffei and Mycobacterium abscessus in a human immunodeficiency virus-negative patient with anti-interferon-γ autoantibody: a case report

“…Taralomycosis is a rare opportunistic infection typically affecting immunocompromised or immunosuppressed patients. The condition is rarely observed in immunocompetent patients and in nonendemic regions outside of Southeast Asia and southern China, [10][11][12] such as Hangzhou, North Zhejiang Province, East China. Therefore, we first assessed the presence of underlying immune deficiencies in our patient such as acquired immunodeficiency syndrome, connective tissue diseases, hematological malignancies and immunosuppressants.…”

Talaromycosis in a renal transplant recipient returning from South China

“…Primary lung cancer and post‐transplant lymphoproliferative disease were considered in the differential diagnosis. On‐site cytopathology facilitated the eventual diagnosis 8 . The findings were relayed to the microbiology laboratory prior to sample processing.…”