Boop

Bronchiolitis Obliterans Organizing Pneumonia: BOOP

The characteristic of organizing pneumonia is the appearance of granulized tissue in the distal bronchioles. BOOP can be classified by 1) its cause 2) the cause is undetermined 3) its cryptogenic organizing pneumonia (idiopathic type). About one-half of all cases of BOOP are idiopathic. BOOP on x-ray can also be confused with chronic eosiniphillic pneumonia (CEP). The difference between the two is that BOOP has consolidation in the lower lobes of the lung and CEP consolidation is found in the upper lobes. The definitive diagnosis of BOOP comes down to tissue biopsy.

Conditions that cause BOOP are radiation therapy, infections, drugs/toxins, connective tissue disease, immuno-supressed states, and miscellaneous conditions. The radiation therapy causes BOOP when there is a cancer in the bronchi or breast cancer and the ipsilateral lung develops BOOP. The only common type of infection that causes BOOP is pseudomonas aeruginosa. The other types are coxiella burnetili, mycoplasma, pneumocystis carinii, influenza A, measles, HIV, Chlamydia, plasmodium and parvovirus B19. When BOOP occurs in conjunction with drugs/toxins the common drug causes are minocin, cephalasporins, acebutolol, sulfasalazine, macrodantin, cordarone, tegretol, Dilantin, and betapace. The toxins include L-tryptophan ingestion, sauropus androgynous vegetable poisoning, gold, paint aerosols, nylon flock worker's and silo filler's disease, free-base cocaine, and smoke inhalation. Connective tissue diseases include rheumatoid arthritis, ankylosing spondylitis, ulcerative colitis, Crohn disease, systemic lupus, biliary cirrhosis and thyroiditis. The immuno suppressed causes are commonly due to organ transplantation, cancer, ARDS and AIDS. One of the miscellaneous causes of BOOP is menstrual and pregnancy related.

Clinically, BOOP affects ages 40-70 but has been reported in children.