Cytopathology Conference 12/01/2005

Case 1 Pericardial fluid from a 36-year-old female with a history of lupus and a pericardial effusion.

Pericardial fluid from a 36-year-old female with a history of lupus and a pericardial effusion.

A special stain was performed…

Diagnosis?

Differential Diagnosis Idiopathic pericarditis Lupus pericarditis Pericarditis due to mycobacterium species Pericarditis due to gram negative species

Idiopathic pericarditis

Lupus pericarditis

Pericarditis due to mycobacterium species

Pericarditis due to gram negative species

Lupus Pericarditis: pericardial fluid positive for Mycobacterium mucogenicum

Mycobacterium mucogenicum Designated as a new species in 1995 Member of Mycobacterium fortuitum-chelonae complex. Belongs to group IV of the Runyon Classification of nontuberclous mycobacteria ( NTM ).

Designated as a new species in 1995

Member of Mycobacterium fortuitum-chelonae complex.

Belongs to group IV of the Runyon Classification of nontuberclous mycobacteria ( NTM ).

Mycobacteria Mycobacterium tuberculosis complex Nontuberculous mycobacteria Mycobacterium tuberculosis Mycobacterium bovis Mycobacterium africanum Runyon Classification I) Photochromogens II) Scotochromogens III) Nonphotochromogens IV) Rapid-growers

Mycobacterium mucogenicum All Runyon group IV members: Acid fast Don’t produce pigment Growth: < 7days Produce arylsufatase after 3 days of growth Growth at 28 degrees on crystal violet neg. MacConkey agar

All Runyon group IV members:

Acid fast

Don’t produce pigment

Growth: < 7days

Produce arylsufatase after 3 days of growth

Growth at 28 degrees on crystal violet neg. MacConkey agar

Mycobacterium mucogenicum Identified as a water contaminant in the hospital setting. Nosocomial infections: post-surgical, catheter related, hemodialysis. Commensal organism: found on skin

Identified as a water contaminant in the hospital setting.

Nosocomial infections: post-surgical, catheter related, hemodialysis.

Commensal organism: found on skin

Mycobacterium mucogenicum Identification: Unique 16s ribosomal unit Mycobacterial membrane fatty acid composition: Resistant to INH and rifampin Susceptible in vitro to quinolones, amikacin, imipenim and Bactrim

Identification:

Unique 16s ribosomal unit

Mycobacterial membrane fatty acid composition:

Resistant to INH and rifampin

Susceptible in vitro to quinolones, amikacin, imipenim and Bactrim

Microscopic Appearance I) M kansasii: long, curved or folded and beaded II) M scrofulaceum : very short and delicate III) MAC: short, thick and beaded IV) M fortuitum : long and filamentous

I) M kansasii: long, curved or folded and beaded

II) M scrofulaceum : very short and delicate

III) MAC: short, thick and beaded

IV) M fortuitum : long and filamentous