Search PubMed⌕ Search

Biomedical subjects

A J McAdams

Publications and source records attributed to A J McAdams.

At least 19 recordsLinked to original sources
PubMed1979

Idiopathic rapidly progressive glomerulonephritis with C3 nephritic factor and hypocomplementemia.

A 7-year-old boy with mild renal failure and signs and symptoms of acute poststreptococcal glomerulonephritis including severe hypocomplementemia had, by renal biopsy, numerous crescents but no deposits in the glomerular capillary loops. Instead, deposits identical in location and composition to those described for children with idiopathic rapidly progressive glomerulonephritis were present. The severe hypocomplementemia was found to be due to high levels of C3 nephritic factor; niether nephritic factor nor hypocomplementemia has been reported in rapidly progressive glomerulonephritis of the idiopathic type. Following prompt therapy with methylprednisolone intravenously, serologic abnormalities disappeared and renal function greatly improved, but a later biopsy showed 50% of the glomeruli obliterated by scarring. The case is of importance not only in indicating that severe hypocomplementemia does not rule out idiopathic rapidly progressive glomerulonephritis but also in adding to the list of diseases in which nephritic factor can be found.

Antigen-Antibody Complex↗
PubMed1979

Glomerular deposition of complement-control proteins in acute and chronic glomerulonephritis.

Acute poststreptococcal glomerulonephritis (AGN) differed from membranoproliferative glomerulonephritis (MPGN) and lupus nephritis (SLE) in that two of the proteins that control the C3b-dependent convertase, beta 1H and the C3bC4b-inactivator cofactor (C3bC4bICo), were frequently absent from the glomerular deposits. In addition, factor B was distributed with C3 in the capillary walls in hypocomplementemic AGN patients. From this, it can be assumed that C3bBb is in the deposits, uninhibited by control proteins as would be predicted for alternative pathway activation. Factor B could not be found in normocomplementemic AGN, was rarely present in MPGN, but was usually present in SLE, most often in the mesangium. In MPGN and SLE, the control proteins were nearly always present in the glomeruli in a distribution like that of C3; IN MPGN they were particularly abundant. Complement profiles indicated an occasional transient reduction in serum C4 level early in AGN. Thus, although there is occasional evidence of early classical activation in AGN, more characteristic is a long period of alternative activation. Serum levels of control proteins did not deviate greatly from normal except for reduced serum beta 1H levels in MPGN type I.

Biopsy, Needle↗
PubMed1978

Multifocal nephroblastic neoplasia.

Among 23 patients with multifocal metanephric neoplasia were 14 patients with 43 grossly visible subcapsular tumorlets, 0.3-3.5 cm in diameter, that were apparently derived from nodular renal blastema. Tumorlets are defined as circumscribed lesions that are visible on the exterior surface of the kidney, produce either a raised nodule or, in a few instances, a shallow depression, and are independent of the main tumor(s). Most tumorlets displayed homogeneous epithelial maturation. A substantial minority of tumorlets retained a blastemic character and a few were histologically malignant. Tumorlets tended to be multiple and bilateral but were absent in 9 patients with multifocal disease, including 4 of 10 with bilateral tumors. About half the lesions that achieved tumorlet status, including those that gave rise to clinical tumors, underwent malignant transformation. Contralateral tumorlets should not be mistaken for metastasis and do not adversely affect prognosis. The incidence of neoplasia among young, close relatives of patients with multifocal disease appeared to be excessive, but no clear excess of major anomalies, hemihypertrophy, or minor genitourinary tract anomalies was revealed by a retrospective survey of hospital charts.

Child↗
PubMed1978

Observations on the evolution of idiopathic rapidly progressive glomerulonephritis.

Distinctive deposits of C3, C5 and properdin were identified in the minimally proliferative glomerular lesions of a patient with idiopathic rapidly progressive glomerulonephritis. Biopsies of her renal allograft at times of recurrences of her disease and of five other patients with progressive renal failure but less severe crescent formation showed deposits identical composition and position, giving evidence of a common pathogenesis. The deposits were subepithelial and located in that part of the basement membrane in apposition to the mesangium (capillary waist). Breaks in the basement membrane were often exclusively in this area suggesting the deposits were causative. Ancillary observations suggest that the subepithelial deposits become unidentifiable after the scarring of severe extracapillary proliferation develops. Three of the patients had, in addition, intramembranous dense deposits but in other ways their disease was not characteristic of membranoproliferative glomerulonephritis Type II. Instead, the evidence indicated that all six patients were in early or lage stages of idiopathic (non-streptococcal) rapidly progressive glomerulonephritis.

Basement Membrane↗
PubMed1977

Membranoproliferative glomerulonephritis with disruption of the glomerular basement membrane.

Seven patients with a form of membranoproliferative glomerulonephritis distinct in its glomerular ultrastructure from other forms are described. The use of silver impregnated electron micrographs revealed contiguous subepithelial and subendothelial deposits associated with basement membrane disruption, replication and layering of lamina densalike material. By light and fluorescence microscopy the appearance was distinctive but not diagnostic. Immunohistology consistently showed abundant C3 and properdin in a granular pattern while immunoglobulins and Clq were variably present. Low serum C3 concentrations were observed at some time in each patient, often accompanied by low levels of properdin, whereas the concentrations of Clq and C4 were normal. The patients were indistinguishable in their clinical course from those with other types of MPGN.

Basement Membrane↗
PubMed1976

Shunt nephritis: the nature of the serum cryoglobulins and their relation to the complement profile.

The serum complement profiles of four patients with shunt nephritis indicated classical pathway activation of the complement system. The presence of mixed cryoglobulins was correlated with disease activity and the cryoglobulins were shown to be complement reactive. Antisera to two of the cryoglobulins recognized antigens of the infecting organism, and a specific bacterial antibody was identified in one cryoglobulin, giveing evidence that the cryoglobulins contained immune complexes. Bacterial antibody without detectable antigen was demonstrable in the sera indicating antibody excess. Renal morphology demonstrated mesangial proliferation and interposition with subendothelial and mesangial deposits. Parallels are drawn with active lupus nephritis.

Antigens, Bacterial↗
PubMed1976

The nephroblastomatosis complex and its relationship to Wilms' tumor: a clinicopathologic treatise.

1. At least one third of all children with Wilms' tumors have evidence of aberrant metanephric differentiation, hamartomas, adenomas and nodules of blastema or Wilms' tumorlets in the subcapsular renal cortex. Only the presence of nodular renal blastema was found to correlate with younger age, suggesting that the other tumorlike lesions may be derivatives. 2. In our experience, all patients with bilateral and sequential bilateral Wilms' tumors have exhibited these characteristics in the "uninvolved" renal tissue removed at nephrectomy. 3. Pancortical (infantile), diffuse superficial (late infantile) and multifocal (juvenile) variants of nephroblastomatosis are defined. In the latter 2 forms of nephroblastomatosis the prognosis after modern therapy is at least as good as it is in patients with unilateral, unicentric Wilms' tumor arising in a histologically normal kidney. 4. The morphologic evidence presented strongly indicates that Wilms' tumor in patients with nephroblastomatosis develops either from nodular blastema or metanephric hamartomas. It is hypothetically possible that all Wilms' tumors develop from these precursors. The latent period between cessation of nephrogenesis and clinical presentation of Wilms' tumor is interpreted as favoring the hypothesis that carcinogenesis per se is the result of a postnatal event but that the substrate for tumor development, aberrant metanephric proliferation, has its inception during gestation.

Adenoma↗
PubMed1975

Mesangiocapillary glomerulonephritis: changes in glomerular morphology with long-term alternate-day prednisone therapy.

In all of eight patients with mesangiocapillary glomerulonephritis who received prednisone in an alternate-day schedule for 3 to 9 hr, the glomerule showed a marked reduction in mesangial cellularity and complete regression of mesangial interposition. Subendothelial deposits disappeared but intramembranous dense deposits, when present previously, persisted. Repair was incomplete in that a few mesangial deposits were still present, immunoflourescence was unchanged, and several of the patients developed focal mesangial scarring and increased numbers of global bodies. Functional glomerule and glomerular tuft segments, however, showed greatly improved morphology. There was no evidence of deterioration of renal function over a follow-up period of 5 to 11.5 yr.

Azathioprine↗