Biomedical subjects
Publications and source records attributed to R Sinniah.
We have presented a rare case of bilateral posterior sphenoethmoidal sinus mucoceles with bilateral compressive optic neuropathy. While the duration of compression was variably present over a 10-month period, there were nevertheless significant improvements in visual acuity of the right eye and visual fields bilaterally following extensive optic nerve decompression.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
The occurrence of glomerular capillary aneurysms in light-chain nephropathy and a morphologic pattern of development as determined by electron microscopy are described. Renal biopsies from 4 patients with nodular glomerulopathy were evaluated. Light-chain deposition in mesangium and capillary walls was associated with monocyte accumulation in capillaries. Loss of endothelial cell lining and disruption of mesangial anchoring points of basement membranes ensued, resulting in aneurysmal dilatation of the capillaries. The walls collapsed, and the aneurysms healed as a result of mesangial interposition, a process which, in combination with enlarging nodules, led to thickening and collapse of the walls and narrowing of the lumens. This study, in conjunction with review of photographs from previously published reports, indicates that glomerular aneurysms are a common feature of nodular light-chain glomerulopathy. It also emphasizes additional light-microscopic similarities between this glomerulopathy and nodular diabetic glomerulosclerosis.
Kidney and liver sections were obtained from 75 consecutive autopsy cases with liver cirrhosis discovered at post-mortem. Mesangial IgA as the predominant immunoglobulin was found in 36% (27) cases, with accompanying IgM in 10, and IgG in three subjects. IgA deposits occurred more frequently in micronodular cirrhosis than in macronodular and mixed types. There was no direct correlation with alcoholism or HBs antigen-orcein positivity in livers. The IgA antigen-antibody complexes formed against infectious and/or dietary antigens may bypass the liver phagocytic system via collateral shunts and cause the mesangial IgA deposits. IgA-bearing plasma cells in the liver (80%) may also contribute to the deposits. In cases of liver cirrhosis, there was a variable glomerular morphology including normal appearance by light microscopy (32%), minor changes (38.7%), diffuse mesangial sclerosis (12%), diffuse mesangial cell proliferation, and infrequently membranous and diffuse proliferative glomerulonephritis with a 'lobular pattern'. Five (6.7%) cases showed focal and segmental mesangiolysis with glomerular aneurysms, probably caused by toxic and/or infective agents bypassing the liver reticuloendothelial phagocytic system and acting on the mesangium to cause rupture of anchor points and formation of capillary aneurysms. The cirrhotic glomerulonephropathy was usually clinically latent, but two biopsy cases with mesangiocapillary glomerulonephritis had developed a nephrotic syndrome.
An 18-year-old 46 XY patient with the syndrome of incomplete testicular feminization was investigated. The clinical phenotypic features were distinctive and typical of the 4 46 XY cases previously reported. The findings of elevated plasma T4 with evidence of incomplete development of female secondary sex characteristics suggest partial end organ insensitivity to the androgen at the target tissues. This possibility is substantiated by the high plasma LH level, presumably the consequence of the relative inability of the hypothalamic-pituitary unit to respond to testosterone in the feedback regulation of LH secretion. It is therefore suggested that, compared to normal males, the patient had an altered hypothalamic-pituitary-testicular function.
Explore the source record for details and available documents.
Kidney sections were obtained from 200 consecutive control necropsies of patients who died of traumatic injuries, with no clinical history of renal disease or other organic disease discovered at necropsy. Mesangial IgA as the predominant immunoglobulin was found in 8/200 (4%) cases, with accompanying IgM in two of them; and IgM alone in two (1%) subjects. Deposits of C3 alone in blood vessels was observed in nine (4.5%) cases. The glomerular morphology was essentially normal or minor change only, with one case showing diffuse mesangial hypercellularity. The high incidence of mesangial IgA deposits in the local apparently healthy population may reflect some common feature of the antigen(s) or complex involved. They may be of environmental, dietary or infectious origin. It is possible that many of these "spontaneous" deposits in the glomerular mesangium may result from the clearance of circulating non-nephritogenic immune complexes.
Malignant tumours with teratoid or blastomatous features are exceptionally rare in the upper respiratory tract with only 8 documented cases, including the 3 in this report. The tumours occurred in adults aged 27 to 62 yr, and the sites of origin were the ethmoid sinus (4 cases), ethmoid and other paranasal sinuses (2 cases), unspecified sinuses (1 case) and nasopharynx (1 case). The disease was rapidly fatal in 3 cases in which treatment was restricted to surgery and was associated with longer survivals in those given supportive radiotherapy. The tumours are locally aggressive and may invade soft tissues, bone, orbit and cranial cavity. Histologically, the tumours are characterized by a mixture of epithelial and mesenchymal components including cellular elements with immature or embryonal characteristics. These tumours, variously termed malignant teratoma, blastoma, teratocarcinoma or teratoid carcinosarcoma, probably comprise a homogeneous group of neoplasms since their histological and biological features are essentially similar. It is postulated that the tumours develop from primitive embryonic tissues or pluripotential cells that have remained sequestered in the sinonasal tract.
In mesangial IgA glomerulonephritis (Berger's disease), the immunoproteins appeared to gain access from the capillary lumen to the mesangium via endothelial fenestrae or via channels between the endothelial cells. The deposits are transported into the deeper mesangium by a process of inhibition or diffusion, with the matrix acting as the head. There are no true channels or grooves in the mesangial matrix for the transport of the immunoproteins. The contractility of the glomerular myoid fibrils may account for the movement of deposits to the hilus for possible removal. There was partial dissolution of the deposits in the mesangial matrix accompanied by loosening of the matrix. No evidence was found for any significant intracellular phagocytosis and digestion. The mesangial deposits directly or indirectly stimulated the cellular hypertrophy and hyperplasia and increased deposition of mesangial matrix. This was accompanied by formation of collagen fibrils within the thickened matrix and led to atrophy of the mesangial cells and sclerosis of the glomeruli.
Explore the source record for details and available documents.
It is generally held that thyroid cancer is uncommonly associated with thyrotoxicosis. We report here nine patients with thyroid cancer amongst 720 patients with thyrotoxicosis. Three patients presented with features of malignancy together with thyrotoxicosis (Group A), one of whom had triiodothyronine (T3)-toxicosis. The remaining six patients were diagnosed following histological examination of tissues removed during subtotal thyroidectomies for hyperthyroidism (Group B). Two patients in Group A had follicular carcinoma; the rest were papillary in type. All the patients were rendered euthyroid initially, followed by ablative therapy for two patients in Group A and four patients in Group B. All but one are alive after one to nine years (mean of 3 . 4 years). The diagnosis of thyroid carcinoma is infrequently considered in the presence of thyrotoxicosis. The association is not clinically apparent in the majority of patients. The optimum management of such occult malignancies in thyrotoxicosis remains to be defined.
Subclinical immune complex glomerular deposits occurred in 20% (11 of 55) of cancer cases examined postmortem. Eight of 11 (72.7%) mucin secreting adenocarcinomas of lung, stomach, large intestine and pancreas showed glomerular mesangial deposits of IgA, with associated IgM and C3 in one-half of them. The glomerular morphology showed predominantly minimal or minor changes, and less frequently mesangial cell proliferation. None of the patients exhibited clinical evidence of glomerulonephritis. The nature of the antigen(s) in the paraneoplastic phenomenon was not defined, but there may have been environmental antigen(s) or specific immune response in the local population to explain the IgA deposition.
Systemic lupus erythematosus (SLE) is a disease of unknown aetiology. Its hallmark is anti-nucleic acid antibodies and it is accompanied by variable clinical, serologic, and histologic signs. Renal involvement in SLE has been documented for over 50 years; it represents one of the most serious complications of this systemic disorder. Although our understanding of the pathogenesis and natural history of lupus nephropathy is still inadequate, it is nevertheless more comprehensive than in most other forms of glomerulonephritis. This paper will review current concepts in the pathogenesis, histologic classification, clinical course, clinico-pathological correlation and therapeutic strategy of lupus nephropathy.
Explore the source record for details and available documents.
Of 710 patients in whom renal biopsies with immunofluorescence, light and electron microscopic and clinical data were available, 239 had idiopathic mesangial IgA nephritis. In these 239 cases IgA was found alone in 45.7%, accompanied by IgG in 50.1%, IgM in 21.4%, C3 in 82.4% and fibrin in 37.2%. Serum immunoglobulin levels including IgA were not significantly raised and complement C3 activation was via the alternative pathway. There was a wide range of glomerular lesions with minor change, minor change with focal and segmental lesions including sclerosis and mesangial cell hypercellularity, diffuse mesangial cell proliferation and, infrequently, diffuse sclerosing glomerulonephritis. The glomerular leions were related to the stage, duration and severity of the disease. There was also a wide variability of clinical presentations, with asymptomatic and symptomatic microscopic haematuria-proteinuria, macroscopic haematuria, recurrent proteinuria, nephrotic syndrome, acute nephritis, hypertension, and uncommonly as acute renal failure and potassium losing nephritis. No aetiological agent was found, and both the streptococcus and HBsAg could not be identified. The disease(s) was the commonest type of primary glomerulonephritis (33.7%) in Singapore, another geographic area in addition to Japan and France, where this lesion has an apparent high incidence.
Explore the source record for details and available documents.
A case of systemic lupus erythematosus is described in which for 10 years the only significant findings were erythema multiforme and vasculitis. Gross hepatosplenomegaly with persistent pancytopenia developed, and bone marrow examination revealed the presence of sideroblasts. The patient's condition deteriorated, and subsequently she developed a severe bleeding tendency, terminating in erythroleukaemia.