Pneumocystis jirovecii: Difference between revisions

From IDWiki
Pneumocystis jirovecii
No edit summary
(: added historical info and other species)
Line 3: Line 3:
 
== Microbiology ==
 
== Microbiology ==
   
  +
* Yeast-like fungus
 
* Previously thought to be ''Pneumocystis carinii'', a close relative that causes disease in rats
 
* Previously thought to be ''Pneumocystis carinii'', a close relative that causes disease in rats
  +
** ''P. carinii'' and ''P. wakefieldiae'' infect rats, ''P. murina'' infects mice and ''P. jiroveci'' infects humans
  +
* Also previously thought to be a protozoan, but reclassified as fungus based on phylogenetic analysis, most closely related to ''Schizosaccharomyces pombe''
   
 
== Epidemiology ==
 
== Epidemiology ==

Revision as of 17:59, 25 September 2019

  • Opportunistic fungal infection of the lower respiratory infection

Microbiology

  • Yeast-like fungus
  • Previously thought to be Pneumocystis carinii, a close relative that causes disease in rats
    • P. carinii and P. wakefieldiae infect rats, P. murina infects mice and P. jiroveci infects humans
  • Also previously thought to be a protozoan, but reclassified as fungus based on phylogenetic analysis, most closely related to Schizosaccharomyces pombe

Epidemiology

  • HIV
  • Immune-suppression, e.g. from steroids

Presentation

  • Shortness of breath on exertion

Investigations

  • CXR
  • Typical: bilateral diffuse patchy disease
  • Atypical:
    • Normal (15%)
    • Localized
    • Pneumothorax
    • Upper lobe, if on pentamidine
  • LDH increased
  • CBC often normal

Diagnosis

  • Induced sputum or brochoalveolar lavage (normal sputum not sensitive enough)
  • 6min walk test: will desaturate, even if well-oxygenated at rest

Treatment

  • Septra 5-6mg/kg po BID for 3 weeks
  • If pO2 <70mmHg or A-a gradient ≥35: prednisone
  • Alternative: clindamycin-primaquine or IV pentamidine
  • Duration is 21 days (3 weeks)

Prophylaxis

  • Usually instituted if the risk of PJP is greater than 3.5% per year

References

  1. ^  Po-Yi Chen, Chong-Jen Yu, Jung-Yien Chien, Po-Ren Hsueh. Anidulafungin as an alternative treatment for Pneumocystis jirovecii pneumonia in patients who could not tolerate Trimethoprim/sulfamethoxazole. International Journal of Antimicrobial Agents. 2019. doi:10.1016/j.ijantimicag.2019.10.001.