The diagnosis of cystic fibrosis (CF) is frequently established for the first time in people your age and older. Serious consideration of CF is definitely warranted, especially since making the diagnosis does not involve invasive procedures. Your history is consistent with that diagnosis.
Another possibility that has recently drawn considerable attention is the combination of immunodeficiency and autoimmune disease, which is discussed in the background section of the abstract below.
-----------------------------------------------------------------------------------------------
Authors
Full Name Coutinho, Antonio. Carneiro-Sampaio, Magda.
Title Primary immunodeficiencies unravel critical aspects of the
pathophysiology of autoimmunity and of the genetics of autoimmune
disease. [Review] [21 refs]
Source Journal of Clinical Immunology. 28 Suppl 1:S4-10, 2008 May.
BACKGROUND: Primary Immunodeficiencies (PIDs) represent unique opportunities to understand the operation of the human immune system. Accordingly, PIDs associated with autoimmune manifestations provide insights into the pathophysiology of autoimmunity as well as into the genetics of autoimmune diseases (AID). Epidemiological data show that there are PIDs systematically associated with AID, such as immune dysregulation, polyendocrinopathy, enteropathy, X-linked syndrome (IPEX), Omenn syndrome, autoimmune polyendocrinopathy-candidiasis-ectodermal dystrophy (APECED), autoimmune lymphoproliferative syndrome (ALPS), and C1q deficiency, while strong associations are seen with a handful of other deficits.
CONCLUSION: We interpret such stringent disease associations, together with a wealth of observations in experimental systems, as indicating first of all that natural tolerance to body components is an active, dominant process involving many of the components that ensure responsiveness, rather than, as previously believed, the result of the mere purge of autoreactivities. More precisely, it seems that deficits of Treg cell development, functions, numbers, and T cell receptor repertoire are among the main factors for autoimmunity pathogenesis in many (if not all) PIDs most frequently presenting with autoimmune features. Clearly, other pathophysiological mechanisms are also involved in autoimmunity, but these seem less critical in the process of self-tolerance. Comparing the clinical picture of IPEX cases with those, much less severe, of ALPS or APECED, provides some assessment of the relative importance of each set of mechanisms. [References: 21]
-----------------------------------------------------------------------------------------------
Finally, there is a category of diseases in which neutrophils and macrophages are functionally defective and unable to kill certain types of bacteria.
The bottom line is that you may have a complex combination of autoimmune and immunodeficiency states or could have CF with immunoglobulin A (IgA) deficiency.
I recommend that you consider requesting a second immunologist’s opinion, at the National Institute of Health (NIH), the Mayo Clinic or National Jewish Health that is a specialty hospital dedicated to the treatment and investigation of respiratory and immunologic diseases in Denver, Colorado.
Good luck.