Hypersensitivity Pneumonias. Wyatt E. Rousseau, MD May 10, 2007. Hypersensitivity Pneumonitis Extrinsic Allergic Alveolitis. A syndrome characterized by diffuse inflammation of lung parenchyma and airways in response to inhalation of antigens to which the patient has been previously sensitized.
Wyatt E. Rousseau, MD
May 10, 2007
Hypersensitivity PneumonitisExtrinsic Allergic Alveolitis
A syndrome characterized by diffuse inflammation of lung parenchyma and airways in response to inhalation of antigens to which the patient has been previously sensitized
Solaymani-Dodaran M, West J, Smith C, Hubbard R. Extrinsic allergic alveolitis: incidence and mortality in the general population. QJM 2007; 100: 233-237.
BH, 50 y.o. WF NS, described three episodes in three weeks of SOB, chest tightness, and hemoptysis. Initial episode lasted 2 hours, asso. with fever and chills, T. to 101F. , and tsp. of bloody phlegm.
PMH: hysterx 1984, on Premarin, Lexapro, Neurontin, trazadone, calcium, Fosamax. Parents both smoked, F d. lung CA, M d. emphysema and bronchiectasis, D with asthma. Pt. had had severe complications of arthroscopy-6 surgeries, 3 ½ years of immobilization until TKR in 12/02, with
lymphedema, but had become quite physically
fit with resting pulse usually 47. On PE, macular, papular rash over abdomen, chest, and neck. No nodes, clear chest, and left leg was not more swollen than right.
She had had chest CT 2/10/04 considered normal, and Lung scan 2/12/04 suggesting airways disease with inhomogeneous perfusion and prolonged washout.
I recommended some lab work including D-dimer, CRP, and a venous doppler. She declined; so I asked her to take a sputum cup to bring in if she coughed and I planned a
CTA ifanother episode. She called the next day after a worse episode of tightness, SOB, and hemoptysis.
CTA 2/17/04 “tree in bud bilateral and diffuse” suggesting infection or inflammation. Bronchoscopy 2/18/07 appeared normal, with biopsies revealing “mild chronic inflammation.” March 4 received report of outpatient sputum growing an AFB, and I assumed MAC, and discussed Abx therapy. She then decided on VATS OLBx. (Bronch and OLBx cultures were both negative ultimately.)
Lung biopsy revealed chronic bronchiolitis/
hypersensitivity pneumonitis (extrinsic allergic alveolitis) with opinion from Mayo Clinic path arriving on 3/30/04. “Hot tub lung due to MAC”. I recommended Prednisone 20 mg. daily, but she had major psychiatric complications for which Seroquel was added and prednisone reduced. X-ray, spirometry, and symptoms resolved. Prednisone tapered and stopped in late May. Recurrence of symptoms and rash in August/September.
Silva CI, Churg A, Muller NL. Hypersensitivity pneumonitis: spectrum of high-resolution CT and pathologic findings. Am J Roentgenol 2007; 188: 334-44.
Lacasse Y, for the HP Study Group. Clinical Diagnosis of Hypersensitivity Pneumonitis. Am J Respir Crit Care Med 2003; 168: 952-958.