Prospective Observational Study Evaluating the Prevalence of Adenosine Deaminase (ADA) Enzyme Deficiency Disease in Adult Patients With Pulmonary Alveolar Proteinosis in Pulmonology Clinics

PAP (Pulmonary alveolar proteinosis) is a rare disease with a frequency of 0.36 per million. As a result of intensive accumulation of surfactant components in the lungs, it leads to respiratory distress at various levels. PAP has been frequently monitored among patients with ADA enzyme deciency. Primary immunodeficiency diseases are a group of diseases that are accompanied by chronic and/or recurrent bacterial, fungal, protozoal and viral infections that develop as a result of primary or congenital immunodeficiency. The incidence dec in society varies from 1/10,000 to 1/100,000. Combined immunodeficiencies account for 15-29% of primary immunodeficiencies. Severe Combined Immunodeficiencies (SCID) are a heterogeneous group of diseases caused by hereditary errors in genes involved in the development and/or function of T, B, and sometimes NK cells, which cause serious dysfunction of the immune system. The incidence is estimated at 1/100,000 live births in the United States. Although the exact incidence of inbreeding is not known in our country, where inbreeding is common, it is expected that those who show autosomal recessive transition will be more common, especially. The recognition of these disorders by clinicians is important for reducing long-term complications due to recurrent infections and preventing mortality with appropriate treatment. The frequency of SCIDY in our country is unknown. Unlike in Europe and America, SCID types, which are autosomal recessive in our country, are considered to be the most common form due to the high rates of inbreeding. The ratio obtained by comparing the number of live babies born in a year in Konya with the number of SCID cases diagnosed in the same year in the Pediatric Immunology Clinic of the Meram Faculty of Medicine of Selcuk University, the only primary immunodeficiency diagnostic center in the region, is 1/10,000. This preliminary study shows that in our country this disease is much more common than in Europe and America. To date, more than 20 genetic defects have been identified that cause SCID. All known genetic defects disrupt the development of cells of the immune system, causing combined immunodeficiency. One of them, the ADA defect, is also a metabolic disease, due to which there is a lack of enzymes. ADA catalyzes the deamination of purine nucleosides adenosine (Ado) and 2'-deoxyadenosine (dAdo), which are produced during the degradation and transformation of RNA and DNA. ADA is a cleansing enzyme: it detoxifies purines. In ADA deficiency, 2'-deoxyadenosine (dAdo) is phosphorylated and converted into deoxyadenosine triphosphate (dATP). Accumulation of DATP disrupts DNA repair and replication. In ADA deficiency, a high percentage of dATP accumulates, especially in erythrocytes and lymphocytes. Increased levels of adenosine break down the wall of the lymphocyte. It inhibits the development of lymphocytes in the thymus. A kind of lymphocyte intoxication occurs. It leads to a severe form of lymphopenia. Approximately 10-20% of SCID are diagnosed as ADA enzyme deficiency. It shows an autosomal recessive transition. Your gene is 20. it is localized on the long arm of the chromosome.

Clinically, there are early and late onset types:

Classic-early onset ADA deficiency: Although normal at birth, patients present with infections seen from the first months of life, resulting in death if left untreated. In addition to the AKI table, neuro-developmental disorders, sensorineural hearing loss and/or skeletal abnormalities have also been reported in these patients. Although hematopoietic stem cell transplantation, enzyme replacement therapy and gene therapy are treatment approaches that provide cure, early diagnosis determines the prognosis.

Late-onset ADA deficiency: Patients may present with recurrent infections, bronchiectasis, autoimmunity, human papillomavirus (HPV) infections at an older age, even in adulthood. Lymphopenia is an invariable finding. High IgE and eosinophilia may be observed. In these cases, residual enzyme activity due to the type of mutation causes a late onset. This phenotype accounts for 10-15% of all cases of ADA deficiency.

Patients with late-onset ADA enzyme deficiency appear in the form of case reports. in a study in which the data of two patients were shared in Zurich in 1997, one patient had a history of recurrent otitis and pulmonary infection, bronchiectasis, lymphopenia, and immunoglobulin E elevation. The other patient, his cousin ADA, was diagnosed by chance while undergoing a bone marrow scan due to enzyme deficiency. He had a history of recurrent tonsillitis.