A 25 y.o. male with a hx of asthma presents with hemoptysis

What do you see on his imaging?

hint: there is narrowing of the L mainstem bronchus

There is calcium in the L hilar nodes

Our patient had fibrosing mediastinitis, in this case defined as IgG 4 related disease because of his biopsy.

IgG4 is is the least abundant IgG subclass accounting for < 5% of total IgG. The molecule plays a role in immune  related conditions. IgG4 -related disease is a chronic inflammatory condition  associated with tissue infiltration of lymphocytes and IgG4 secreting plasma cells triggered by an immune response to an antigen.

plasma cells with typical “clockface” pattern of chromatin are derivatives of lymphocytes

 In the case of fibrosing mediastinitis , the production of IgG 4 is thought to be a response to histoplasmosis, a common fungus of the Ohio and Mississippi river valleys. Connective tissue is formed in response to an antigen, leading to fibrosis and the development of mass lesions.  Several different diseases are now thought to be part of the IgG 4 spectrum including: Mikulicz disease (sclerosis of salivary and lacrimal glands), autoimmune pancreatitis,  interstitial nephritis, retroperitoneal fibrosis, pemphigus vulgaris,, thrombotic thrombocytopenia purpura,  and autoimmune hypophysitis,  as well as fibrosing mediastinitis.

IgG4-related disease can affect any organ. In the lung this fibrosis can lead to venous occlusion and pulmonary infarcts or the development of collateral bronchial circulation. Obstruction of the pulmonary artery can also cause bronchial collaterals to develop.  In some cases the bronchial arteries bleed requiring embolization. While the bronchial arteries account for only 2% of the total vascular supply to the lung they account for 90 % of life threatening hemoptysis(  >300 cc)

IgG4 fibrosis in the prostate causing prostatitis

A REVIEW OF HEMOPTYSIS

The lung has two sources of blood supply the pulmonary artery and the bronchial arteries. It is important to determine whether hemoptysis comes from the pulmonary artery supplying the lung( a low pressure system) or the bronchial arteries( a high pressure system.)  While the bronchial arteries account for only 2% of the total vascular supply to the lungs, they account for 90% of life threatening bleeding.  To be clear, most hemoptysis is NOT life threatening with bronchitis and infection being much more common than bronchial artery bleeding.  Causes of hemoptysis are listed below. 

Our patient received high dose steroids and his bleeding resolved. 

 Kobraei E, song T, Mathisen D, et al. Immunoglobulin G4-related disease presenting as an obstructing tracheal mass consideration of surgical indications. 2013. Annals of thoracic Surgery. 96(4): e91-93.  Soi:10.1016/j.athoracsur 2013.04.120

Patel M, Lu F, Hannaway M. Hochman K. Fibrosing mediastinitis: a rare complication of histoplasmosis. 2015  BMJ Case Rep published online 2015 Nov 4 doi:10.1136/bcr-2015-212774.

Sedhom R, Sedhom D, Strair.  IgG-4 related disease: A mini-review 2017. Journal of Rare diseases Ressearch & Treatment  . Feb 11.