Bronchiectasis-related amyloidosis as a cause of chronic renal failure

Bronchiectasis is defined as acquired and permanent abnormal dilation and destruction of the bronchial walls. Secondary amyloidosis is a disorder characterized by the deposition of amyloid A (AA) in multiple organs and tissues in the body. End-stage renal disease (ESRD) secondary to bronchiectasis-related amyloidosis has only been mentioned in case reports. Little is known about the complications of bronchiectasis-related amyloidosis and the outcomes in patients who develop ESRD due to amyloid deposition in the kidneys. The aim of this study was to identify the clinical characteristics of this patient group, and to report the outcomes of these cases relative to bronchiechtasis type. We assessed the records of 40 patients with AA-type amyloid nephropathy and ESRD who were on hemodialysis (HD) at Baskent University Hospital between 1997 and 2000. The diagnosis of amyloidosis was based on histopathological findings in kidney, rectum, bone marrow, lymph node, thyroid, bladder, liver, and stomach biopsies. Bronchiectasis was diagnosed on the basis of history and findings on physical examination, chest X-ray, and thoracic high-resolution computerized tomography (HRCT). The patients' records were retrospectively evaluated for cause of secondary amyloidosis, and cases with causes other than bronchiectasis were excluded. Secondary amyloidosis due to bronchiectasis and recurrent pulmonary infection was identified in 40% (16 patients) of the 40 patients. For each of these 16 cases, we recorded patient age, duration of bronchiectasis, duration of HD, amount of lung involvement, and biopsy site(s). The means for age, duration of bronchiectasis, and duration of HD in the 16 patients were 50.6 +/- 13.5 years, 22.18 +/- 12.02 years (range, 6-42 years), and 30.81 +/- 36.94 months (range, 4-144 months), respectively. The most common biopsy site was the rectum (n = 8). Thoracic HRCT revealed cystic bronchiectasis in 8 cases (50%). Four of these 8 patients (25% of the group of 16) died from sepsis within 3-year follow-up period. Two of the four patients who died had bilateral cystic bronchiectasis, and the other two had unilateral cystic bronchiectasis. In the other eight patients in the group, thoracic HRCT showed chronic fibrotic changes in the pulmonary parenchyma and minimal traction bronchiectasis. Four of these patients exhibited apical fibrosis and bronchiectasis (25% of the group of 16), and these radiological findings were considered sequelae of previous tuberculosis infections. In conclusion, chronic respiratory infections and associated bronchiectasis remain a serious problem in Turkey due to insufficient prevention, diagnosis, and treatment. It is important that patients with progressive cystic and diffuse bronchiectasis be followed carefully, as they may develop amyloidosis and ESRD in time. Also, the clinical course in patients with cystic bronchiectasis may be worse than that in other types of bronchiectasis due to complicating pulmonary infections.