An analysis of cutaneous amyloidosis cases during a five year period, from January 1, 1983 to December 31, 1987, showed that of 78 cases suffering from lichen amyloidosis, 9 patients (11.5%) were male and 71 patients (80.5%) female. Macular skin amyloidosis was observed. Sixty patients (76.9%) were found in the age range of 20-50 years. Forty-nine patients (62.8%) suffered from the disease for 2 years or less. Skin changes were mainly located on the shin areas, the posterior part of the lower thighs and posterior part of the forearms. Treatment with strong topical corticosteroids and keratolytic agents (salicylic acid ointment in higher than 3%) proved to be unsatisfactory. The literature mentions higher incidence of lichen amyloidosis in Chinese, Malaysians and Indonesians than in Caucasians.
Congo red screening of routine biopsies at the University Hospital Kuala Lumpur revealed the following categories of amyloidosis: systemic AL (5.9%); systemic AA (3.2%); isolated atrial (14%); primary localized cutaneous (7.5%); other primary localized deposits (3.2%); localized intratumour (58%); and dystrophic (8.6%). Unlike in the West, AA amyloidosis in this population was usually secondary to leprosy or tuberculosis. Liver involvement in AL amyloidosis was shown to exhibit a sinusoidal pattern and differed from the vascular pattern of AA amyloidosis. Within the category of AA amyloidosis, there were two patterns of renal involvement--glomerular and vascular, with the glomerular pattern carrying a more ominous clinical picture. Notable among the localized amyloidoses were isolated atrial amyloidosis complicating chronic rheumatic heart disease, intratumour amyloidosis within nasopharyngeal carcinomas and dystrophic amyloidosis which occurred in fibrotic tissues.
Nineteen out of 121 consecutive cardiac biopsies from 107 patients were found to contain amyloid deposits on routine Congo red screening. Seventeen were left atrial appendages removed during mitral valvotomy for chronic rheumatic mitral valve disease while the remaining two were right atrial appendages excised during surgical repair of atrial septal defects. The distribution of amyloid deposits within the atria and their tinctorial characteristics are described. The high prevalence of atrial amyloidosis observed could not be attributed to generalized or senile amyloidosis. The possibility that this is a distinctive localized form of amyloidosis secondary to chronic heart disease is discussed.
Congo red screening of 27,052 routine biopsy specimens from 22,827 patients over a 5 1/2-year period in the Department of Pathology, University of Malaya detected 186 cases of amyloidosis. The categories of amyloidosis encountered and their prevalences in relation to each other were: systemic AL (5.9%); systemic AA (3.2%); isolated atrial (14%); primary localized cutaneous (7.5%); other primary localized deposits (3.2%); localized intratumour (58%); and dystrophic (8.6%). A third of patients with systemic AL amyloidosis had coexistent immunocyte abnormality. The commonest underlying pathology for systemic AA amyloidosis was leprosy. Notable among the types of localized amyloidosis revealed by this study were isolated atrial amyloidosis, which appeared to complicate chronic rheumatic heart disease, and intratumour amyloidosis complicating nasopharyngeal carcinoma. Other tumours in which amyloid deposits were observed included basal cell carcinoma, islet cell tumour and medullary carcinoma of the thyroid. Dystrophic amyloidosis was observed in fibrotic tissues, such as damaged cardiac valves and osteoarthritic joints. Heredofamilial amyloidosis, senile systemic amyloidosis and degenerative cerebral amyloidosis were notably absent from this study.
Material from 334 consecutive autopsies on Orang Asli subjects performed in the University Hospital, Kuala Lumpur between May 1967 and June 1978 was examined for amyloidosis. Nine positive cases were found, all in patients above 40 years of age, giving an age-corrected incidence of about 9%. In 6 cases, amyloidosis was probably secondary to tuberculosis. The remaining 3 cases exhibited a pericollagenous distribution characteristic of primary amyloidosis. Involvement of the heart and lungs was prominent. However, there were considerable similarities in the distribution and staining properties of the amyloid in the 2 groups. Though both the heart and kidney were frequently affected, the kidney was the most common organ to give rise to clinical symptoms. Infection probably plays a major contributory role in amyloidosis in the Orang Asli.
Congo red screening of tissue blocks from 37 consecutive autopsies on leprosy patients revealed 7 cases of systemic amyloidosis, indicating a prevalence rate of 19%. 5 were males and 2 females. All were ethnic Chinese. Their ages ranged from 52 to 85 years with a mean of 69 years. Six had lepromatous leprosy while the remaining 1 had tuberculoid leprosy. In all 7 cases, the amyloid was AA in type, being permanganate-sensitive and immunoreactive with anti-human AA protein antiserum. Hepatic deposition was limited to blood vessels, a pattern typical of AA (secondary) amyloidosis. With regard to renal involvement, 4 showed a predominantly vascular pattern of infiltration while 3 exhibited the more ominous glomerular pattern. Three died of chronic renal failure and 2 of congestive cardiac failure attributable to renal and cardiac amyloidosis respectively. One patient succumbed to septicaemia and the remaining 1 to acute myocardial infarction. AA amyloidosis remains a serious and significant complication of leprosy among Malaysians.
Congo red screening of 211 consecutive cardiac biopsy specimens obtained during cardiac surgery from 167 patients revealed 26 (16%) instances of isolated atrial amyloidosis (IAA). The ages of IAA-positive patients ranged from 25 to 52 years (mean age, 39 years). Twenty-three (88%) IAA-positive biopsy specimens were from patients with chronic rheumatic heart disease (CRHD) while three (12%) were from patients with an atrial septal defect (ASD). The prevalence of IAA in the CRHD patients was 23%, appreciably higher than that in the ASD patients (15%) and in other patients with atrial biopsies. The prevalence of IAA in both CRHD and ASD patients was significantly higher (P < .001) than in controls. Controls consisted of 247 healthy adults who were autopsied after traumatic deaths, with an age range of 18 to 89 years (mean age, 38 years). Only seven (3%) control subjects were IAA positive; all were over 40 years of age. Isolated atrial amyloidosis deposits were permanganate resistant and immunohistochemically positive for human amyloid P (AP) protein and negative for human amyloid-associated (AA) protein and immunoglobulin light chains. They were observed as fine congophilic and birefringent deposits in intramyocardial vessel walls, along the myocardial sarcolemma, and in the subendocardium. There was associated myocyte hypertrophy but no atrophy. Electron microscopy demonstrated typical nonbranching amyloid fibrils. It is postulated that stretching of the atria in chronic heart disease results in a raised prevalence of IAA. Recent reports that IAA contains atrial natriuretic peptide, a polypeptide hormone product of atrial myocytes, supports this view.