Fascinoma Rounds Penicillium marneffei

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Fascinoma RoundsPenicillium marneffei

• October 26th, 2005
• Sharmistha Mishra,
• Vanessa Allen,
• And with great thanks to Subash Mohan

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Case 1 Penicillium marneffei

• What are the clinical risk factors for acquiring
  disseminated penicillium marneffei?
• What are the laboratory features of this organism
  (courtesy of Subash Mohan)?
• What precautions should be taken in the
  laboratory environment?

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Clinical Case

• 32 M originally from Vietnam, no known PMH
• Moved to Canada 16 years ago
• Travel to Vietnam every year,
• last trip in January/ February 2005
• Illness since March/April 2005
• Cough, SOB and 18 lb weight loss
• went to family MD and to a local hospital
  treated for CAP with azithromycin
• V/Q scan negative
• CT scan consistent with CAP
• Also had two month history of non-pruritic
  papular rash on face which he attributed to
  lobster allergy

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Case continued

• Sept 22nd
• Presented with SOB, fever, and bilateral chest
  infiltrates
• Started on Ceftraixone and azithromycin for CAP
• Laboratory values
• Hgb 95 (MCV 75), Leuk 4.4 (0.3 lymphs), platelets
  233
• Electrolyes and creatinine normal
• AST 113, ALT 109, ALP 100, bili 5
• LDH 514

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Case 3

• Bronchoscopy Sept 23rd
• Positive for H. influenza
• PCP
• And .Penicillium marneffei
• Blood cultures from Sept 22nd became positive for
  Penicillium marneffei
• Subsequent HIV , CD4 32

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Discovery

• 1956 ? bamboo rats in Vietnam
• First human case accidental innoculation in the
  lab (1959) from a needle
• Then 1973 ? in pt with Hodgkins disease
• 1985 pt with HIV in tropical medicine course ?
  suspicion of inhalation of spores!
• 1988 onwards ? rising of cases in HIV pts from
  endemic areas

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Epidemiology

• Bamboo rat association unclear
• Soil exposure felt to be a risk factor
• Inhalation, ingestion, skin puncture - postulated
• Geographical distribution
• Thailand, Myanmar (Burma), Vietnam, Cambodia,
  Malaysia, northeastern India, Hong Kong, Taiwan,
  and southern China
• Imported disease from patients from these endemic
  regions

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Clinical Risk Factors

• More commonly seen in immunocompromised (also
  occurs in immunocompetent individuals)
• 29 cases diagnosed 1959-1988 prior to HIV
• Now ? 80 have HIV
• CD4 lt 70 cells/mm3
• Among HIV pts in N. Thailand
• 1. TB
• 2. Cryptococcal meningitis
• 3. Penicillium marneffei
• Other risk factors are lymphoproliferative
  disorders, bronchiectasis and tuberculosis,
  autoimmune diseases and corticosteroid therapy

Supparatpinyo K, et al.. Lancet.
1994344110-113.
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Clinical Features

• Localized disease
• Disseminated disease
• Fever (99)
• Anemia (78),
• Pronounced weight loss (76)
• Generalized lymphadenopathy (58)
• Hepatomegaly (51).
• Skin lesions, most commonly papules with central
  necrotic umbilication (71)
• Pneumonia (CXR abnormalities)

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Penicillium marneffei
Penicillium marneffei is a dimorphic fungus of RES
Grows as mycelium at RT and yeast at 370C
Usually attacks immunocompromised hosts
P. marneffei can also attack immunocompetent hosts
Reservoir bamboo rat in south east Asia
Laboratory safety precautions similar to
Coccidioides
Direct microscopy frequent confusion with
Histoplasma
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Penicillium marneffei

• Direct Microscopy
• Specimen BAL
• (E1232193)
• Stain Fungi-Fluor x400
• Structure
• small, round, oval cells
• non-budding cells
• Compare with yeast.
• Rule out histoplasma.
• Differentiation difficult.

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Penicillium marneffei

• Direct Microscopy
• Specimen BAL
• (E1232193)
• Stain Gram stain x1000
• Structure
• few oval cells
• non-budding
• mimic yeast
• Observe septum

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Penicillium marneffei

• Direct Microscopy
• Specimen BAL
• (E1232193)
• Stain KOH x400
• Structure
• cluster of cells
• poorly differentiated
• appear non-budding
• Rule out yeast
• Interpretation difficult

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Penicillium marneffei

• Direct Microscopy
• Specimen Blood
• Stain Gram stain x1000
• (E1221874)
• Structure
• septate hyphae
• right angle branching
• fragmenting
• Arthroconidia
• Appear converted
• Observe branched pattern
• Not dichotomous

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Penicillium marneffei

• Direct Microscopy
• Specimen Sputum
• Stain GMS x1000
• (E1222049)
• Structure
• cluster of small, round, oval cells
• non-budding
• bisected cells
• Septum rules out yeast
• Suspect P. marneffei

A second type yeast not P. marneffei
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Penicillium marneffei

• Direct Microscopy
• Specimen Sputum
• Stain GMS x1000
• (E1222049)
• Structure
• bisected cells
• no budding seen
• no septate hyphae
• no pseudohyphae
• Go ahead and call it
• P. marneffei

non-budding bisected cells
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Penicillium marneffei

• Macroscopic Morphology
• Medium IMA
• Morphology
• rapid growth
• mycelial phase
• red pigment
• suspect P. marneffei
• Not all red pigmentproducing Penicillium species
  are Penicillium marneffei

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Penicillium marneffei

• Microscopic morphology
• Stain Lactophenol x400
• Structures
• phialides
• metulae
• bi- or univerticiallate
• brush type
• ID Penicillium sp.
• Compare with Paecilomyces

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Penicillium marneffei

• Conversion to Yeast Phase
• Medium Blood agar
• Incubation 370C
• glabrous matted
• no mycelium
• yeasty consistency
• pigmentation lost
• Conversion phase at highertemperature is
  essential forconfirmation
• DNA probe not available

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Penicillium marneffei

• Confirming conversion
• Wet Preparation BA 370C
• Magnification x1000
• Structures
• arthroconidia
• multiplies by fission
• bisected cells
• Compare with yeast and pseudohyphae

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Treatment

• Sensitive to Itraconazole, Ketoconazole and Ampho
  B
• Failure rates in a study of 86 HIV-infected
  patients were as follows amphotericin B , 8 of
  35 patients (22.8) itraconazole , 3 of 12
  (25) and fluconazole , 7 of 11 (63.6)
• Current recommendation
• Amphotericin B, 0.6 mg/kg/day for 2 weeks,
  followed by itraconazole, 400 mg/day orally in
  two divided doses for the next 10 weeks
• 97.3 effective in 74 HIV individuals

Sirisanthana T, Clin Infect Dis.
1998261107-1110.
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Lab Safety and Penicillium marneffei

• No formal guidelines
• Inhalation and direct inoculation are possible
  mechanisms of transmission in lab.