Thank you to Amy Ni, our rockstar pulmonology consultant, for presenting a very interesting case of a patient with an upper lobe cavitary lesion, whose work up revealed a diagnosis of pulmonary coccidioidomycosis.
- While there are many etiologies of cavitary lung lesions, TB should be strongly considered as a highly likely diagnosis, especially in the patient population at ZSFG. (See below for details).
- Think about pulmonary coccidiodomycosis in patients with cavitary lesions with negative AFB smears and negative GeneXperts who had had exposure in endemic areas.
- There are many ways to test for coccidiodomycosis, and the diagnostic approach is driven by localizing symptoms but Cocci can be found in serum, CSF, and in sputum samples or BAL
DDx for Cavitary Lung Lesions:
- What Causes a Cavity?
1) NecrosisSuppurative necrosis – pyogenic abscessCaseous necrosis – tuberculosisIschemic necrosis – pulmonary infarctionMalignant necrosis – treatment related necrosis, internal liquefaction of tumor2) Cystic Dilation of Lung – ball valve lesion3) Replacement of Lung with Cysts – ex/ echinococcus infectionNon-Infectious Causes of Lung Cavities:1) Malignancya. Primary lung malignancyb. KS and lymphomac. Metastatic Cancer to lung2) Rheumatologic Diseasea. GPA (49% with cavitary nodules and 17% with cavitary consolidations in one study)b. Sarcoid (rare cavitation of nodules)3) Various Others – PE with pulmonary necrosis, cryptogenic organizing pneumonia, pulmonary Langerhans’ cell histocytosisInfectious Causes of Lung Cavities:1) Mycobacterial Infectiousa. TB – cavities can be multiple and occurring in areas of consolidationb. NTM – more likely to be cavitary lung nodules2) Necrotizing Bacterial PNA and Lung Abscessa. S. aureus and Klebsiella PNA are more common causesb. S. pneumo and H. flu with CAP, but uncommon3) Uncommon Bacterial Infectionsa. Actinomycosisb. Meliodosis (ask LT about this one!)c. Rhodococcus equi4) Fungal Infectionsa. Aspergillosisb. Histoplasmosis, blastomycosis, coccidiomycosis, paracoccidiomycosis
Link to Great Article on Cavitary Lung Lesions: http://cmr.asm.org/content/21/2/305.long
Where Exactly Is Coccidioidomycosis Endemic?:
- Occurs in 4.7% of recognized cocci infections, 0.2% of all respiratory infections
- Individuals of African of Filipino ancestry or immunosuppressed patients are at greater risk of extrapulmonary infection
- Common Sites
- Skin or subcutaneous tissues
- Joint involvement – often a single joint
- Vertebral infection – may be single or multiple joints
- Meninges – very serious if seen here
Cocci Diagnostic Options:
- Serum: Cocci Ab Immunodiffusion test – screening serum test (IgM and IgG)
- Not helpful if already confirmed from
- Serum Cocci Ab Complement Fixation test – can provide a titer that can be followed
- CSF: Cocci Ab Complement Fixation – can provide a titer that can be followed
- Consider LP and testing if any Neurologic change or Altered mental status and confirmed Cocci in another location
- -Sputum/Biopsy of Affected Organ: histopathology (visualizing spherules) or culture
- Gadkowshi LB and Stout JE. (2008). Cavitary pulmonary disease. Clinical Microbiology Reviews. 21(2): 305-333.
- CDC Map: https://www.cdc.gov/fungal/diseases/coccidioidomycosis/causes.html
- Cavitary Lung Disease: https://www.evernote.com/shard/s509/sh/4527dd88-40e4-4aa0-9ec8-4bad276419be/7f247396c07258b0415e725ea4173222
- Cocci Info: https://www.evernote.com/shard/s509/sh/ed7a2003-57db-4966-a7b9-40847d8f18cb/7607e766e7a851750b4fbef67a88600a