The patient was a 63-year-old Vietnamese man with history of HIV/AIDS who was brought to the emergency department by the family after he was found down in his home for an undetermined amount of time. Two years prior to presentation the patient was hospitalized with Pneumocystis jirovecii pneumonia. During that hospital course, he was diagnosed with HIV infection. His initial absolute CD4 cell count was 64 cells/muL and HIV RNA viral load was 830,000 copies/mL. He was started on antiretroviral therapy with emtricitabine/tenofovir alafenamide and darunavir/cobicistat. However, he discontinued all the medications and was lost to follow up within 2 months after discharge. He immigrated to Missouri in the United States as a tailor approximately 20-25 years prior to this encounter. He visited Vietnam last one year prior to presentation to meet with his family in Mekong Delta, the southernmost part of Vietnam, and has never traveled anywhere except Vietnam.
On presentation, he was febrile with a temperature 39  C, respiratory rate 24 breaths per minute, and heart rate 115 beats per minute. Blood pressure was normal. Patient was alert, but oriented to person only and appeared confused. Physical examination showed normal heart, lung, abdominal, and neurological examinations. He had no skin lesions. Laboratory findings showed a platelet count 8,000 /muL and white blood cell count (WBC) 4,700 /muL. Lactic acid was elevated to 5.9 mmol/L (reference range: 0.5-2.2 mmol/L). Computed tomography (CT) of the head without contrast showed no acute intracranial findings. However, it incidentally revealed a right tonsillar mass with surrounding right cervical lymphadenopathy, and he admitted the presence of throat pain. CT angiogram of the neck was obtained which showed an ill-defined mass along the right lateral aspect of the hypopharynx involving the base of the tongue, right lingual tonsil, and right vallecula extending along the right palatine tonsil and into the pharyngeal space (Fig. 1). Magnetic resonance imaging of the brain showed findings consistent with sequela of HIV encephalopathy.
Cerebrospinal fluid (CSF) study showed WBC 5 cells/muL, red blood cell count 305 cells/muL, protein 45 mg/dL, and glucose 45 mg/dL (serum glucose 90 mg/dL). CSF multiplex polymerase chain reaction testing was negative for E. coli K1, Haemophilus influenzae, Listeria monocytogenes, Neisseria meningitidis, Streptococcus agalactiae, Streptococcus pneumoniae, Enterovirus, Human simplex virus (HSV) 1, HSV 2, Cytomegalovirus (CMV), Varicella-Zoster virus, Human herpesvirus 6, Human parechovirus, and Cryptococcus neoformans/gattii. CSF Cryptococcal antigen (Ag) was negative. HIV RNA viral load was 1,620,000 copies/mL and absolute CD4 cell count was 46 cells/muL. Urine Histoplasma Ag, serum galactomannan assay, serum Cryptococcal Ag, viral hepatitis serologies, T-spot TB  test and Toxoplasma IgM and IgG antibodies were all negative. Serum CMV DNA viral load was 13,680 IU/mL, and serum Epstein-Barr virus DNA viral load was 2,644 copies/mL. Bacterial, fungal, and acid-fast bacilli (AFB) blood cultures were all negative. He was started on intravenous ganciclovir 5 mg/kg every 12 h for CMV viremia and became afebrile.
He underwent direct flexible laryngoscopy for the biopsy of the tonsillar mass and the base of the right tongue. An ulcerative and friable mass involving the right palatine tonsil wall was found and it appeared malignant. However, histology of the right tonsillar mass showed squamous epithelium with acute and chronic lympho-histiocytes, inflammation with crusting, and ulcer formation, and Grocott methenamine silver (GMS) stain revealed presence of yeast. The yeast cells were small (2-5 mum in diameter) and oval to ellipsoidal. The histology of the base of the right tongue showed noncaseating granulomas with intense chronic inflammation as well as yeast on GMS stain. AFB and Warthin-Starry stains were negative. Flow cytometry showed no evidence of lymphoproliferative disorder. Five days later fungal cultures incubated at 25  C on Sabouraud dextrose agar grew suede-like grayish-white colonies with diffusible underlying deep red color pigment (Fig. 2). Microscopically, flask-shaped phialides in brush-like arrangement were seen on lactophenol cotton blue staining (Fig. 3). The culture isolate was sent to a reference laboratory and confirmed as Talaromyces marneffei.
The patient was treated for T. marneffei infection with intravenous liposomal amphotericin B 4 mg/kg intravenous every 24 h for 2 weeks followed by oral itraconazole 200 mg twice a day. His throat pain resolved with significant decrease in the size of the tonsillar mass.