Q:

7/17/2013
I have a patient who has worked in a cheese factory for about 8 months. Within a couple months or starting, she began to develop dyspnea in the workplace. There is some cough, but she believes that the cough is just part of her attempts to get more air. She has been treated with various antibiotics and asthma medications, including ADVAIR, by her PCP without much benefit. The only medication that she believes helped some was prednisone although the benefit was transient. She was referred for allergy and asthma evaluation.

She has no prior history suspicious for allergies or asthma. The onset of her symptoms was gradual. There was not an initial, acute, febrile episode. She works four, 10-hour shifts in a factory that makes blue cheese and is then off for 3 days. She does not experience the dyspnea while at home. Percutaneous allergy testing for common environmental allergens was unremarkable. Spirometry was normal although the patient was still on ADVAIR. The patient is scheduled for a methacholine challenge. Cheese mold IgE and IgG was ordered through Viracor/IBT. Cheese mold IgE was negative. Cheese mold IgG was 10.4 mcg/mL. I understand that this does not necessarily mean that she has hypersensitivity pneumonitis and may just be evidence that she has had exposure.

I have two questions. First, do you know of any labs that could perform an immunodiffusion test to further evaluate this patient for reactivity to the Penicillium molds used in making blue cheese? Additionally, is there anything else that you would consider doing?

A:

Thank you for your inquiry.

In answer to your first question, the National Jewish Health Laboratory does have the test (Catalog Number M11, entitled Precipitin Penicillium Mix IgG).

In answer to your second question, since what you would be dealing with is an alveolitis (the alternative name for hypersensitivity pneumonitis is extrinsic allergic alveolitis), one would clearly expect a defect in the DLCO. Thus, if you have not done complete pulmonary functions with DLCO, I believe that would be in order. If the DLCO is normal, it mitigates strongly against the diagnosis unless the disease is at its very earliest phase. But even at the earliest phase, the DLCO usually decreases with exercise. You might also, therefore, consider a pulse ox, both at rest and with exercise, in your office. Finally, a high resolution computed tomography scan would almost universally be abnormal because alveolar changes, even at the earliest phase, should be present.

Finally, as you mentioned earlier about IgG anti-penicillium, precipitin anti-penicillium (IgG or IgM), although very sensitive, are also found in many patients without disease who are exposed. So they are highly sensitive, but not very specific.

Thank you again for your inquiry and we hope this response is helpful to you.

Sincerely,
Phil Lieberman, M.D.

AAAAI - American Academy of Allergy Asthma & Immunology