Correspondence

Bone Marrow Diagnosis of Penicilliosis

N Engl J Med 1994; 330:717-718March 10, 1994

Article

To the Editor:

Penicillium marneffei is a dimorphic fungus that can infect either immunocompromised or healthy people. The infection is most likely to be seen in Asians,1,2 particularly in the setting of AIDS3,4. The diagnosis may be difficult, since the infection is sometimes mistaken for drug-resistant tuberculosis2. We report a case of penicilliosis that was diagnosed by bone marrow examination.

A 26-year-old heterosexual Chinese man who was infected with the human immunodeficiency virus was evaluated for fever and hepatosplenomegaly. Examination of a peripheral-blood sample revealed a hemoglobin level of 5.2 g per deciliter, a leukocyte count of 3900 per cubic millimeter, and a platelet count of 53,000 per cubic millimeter. Examination of a bone marrow aspirate showed a normocellular marrow with adequate megakaryocytes, active erythropoiesis, and granulopoiesis. Many of the histiocytes were engorged, with inclusions measuring 2 to 6 micrometers in diameter that were round or oval to sausage-shaped and contained reddish purple dotlike structures and sometimes transverse septa (Figure 1AFigure 1Bone Marrow Aspirate and Peripheral-Blood Sample from a Patient with Penicilliosis.). The inclusions were stained with periodic acid-Schiff and methenamine silver stains. Occasional circulating monocytes with similar inclusions were also seen (Figure 1B). Cultures of blood and bone marrow confirmed the diagnosis of P. marneffei infection. Treatment with amphotericin B was started, and the patient's fever subsided. Examination of a bone marrow aspirate obtained three weeks after the initial evaluation showed histiocytes with ingested P. marneffei, but no extracellular organisms. No organisms were found when a third bone marrow aspirate was examined 12 weeks later. Blood cultures obtained after four weeks of antifungal treatment were negative. Five months after diagnosis, the patient was still alive.

Bone marrow examination sometimes permits the prompt diagnosis of opportunistic infection in patients with AIDS5. Infections with P. marneffei must be distinguished from those due to Histoplasma capsulatum and Toxoplasma gondii. Septate and elongated yeast forms are characteristic of P. marneffei, whereas narrow-based unequal budding is seen in H. capsulatum. Neither septa nor yeast forms occur in T. gondii. Histoplasmosis is rare in Asian countries, whereas P. marneffei infection is endemic in Southeast Asia2,4. Penicilliosis should be considered as a possible explanation for fever in patients with AIDS, particularly Asians and those with a history of travel in Asia. Prompt treatment with antifungal agents can be lifesaving4.

K.F. Wong, M.B., B.S.
D.N.C. Tsang, M.B., B.S.
J.K.C. Chan, M.B., B.S.
Queen Elizabeth Hospital, Kowloon, Hong Kong

5 References

1. 1

   Jayanetra P, Nitiyanant P, Ajello L, et al. Penicilliosis marneffei in Thailand: report of five human cases. Am J Trop Med Hyg 1984;33:637-644
   Web of Science | Medline

2. 2

   Tsang DN, Chan JK, Lau YT, Lim W, Tse CH, Chan NK. Penicillium marneffei infection: an underdiagnosed disease? Histopathology 1988;13:311-318
   CrossRef | Web of Science | Medline

3. 3

   Tsang DN, Li PC, Tsui MS, Lau YT, Ma KF, Yeoh EK. Penicillium marneffei: another pathogen to consider in patients infected with human immunodeficiency virus. Rev Infect Dis 1991;13:766-767
   CrossRef | Medline

4. 4

   Supparatpinyo K, Chiewchanvit S, Hirunsri P, Uthammachai C, Nelson KE, Sirisanthana T. Penicillium marneffei infection in patients infected with human immunodeficiency virus. Clin Infect Dis 1992;14:871-874
   CrossRef | Web of Science | Medline

5. 5

   Wong KF, Ma SK, Chan JK, Lam KW. Acquired immunodeficiency syndrome presenting as marrow cryptococcosis. Am J Hematol 1993;42:392-394
   CrossRef | Web of Science | Medline