Frohnert, Peter P.

AbstractBackgroundIgA Nephropathy (IgA N) is one of the most common glomerulopathies and may lead to renal failure in 10–20% of cases. After renal transplantation, IgA N has a strong tendency to recur in the graft. Initially considered a benign condition, graft losses from recurrent IgA N have been reported over the last 20 yr, casting doubt on the initial premise. Since large single‐center studies of the fate of renal allografts in IgA N are rare and the Mayo Clinic transplant experience for IgA N is extensive (dating back to 1970), a review of these issues appeared worthwhile.MethodsA retrospective study was done of all renal transplant patients who had had biopsy‐proven IgA N as underlying disorder. We extracted data on the underlying disease, history leading to renal transplantation, factors affecting transplant outcome, and on the course after transplantation with special attention to rejection activity and recurrence of the primary disease. Standard statistical methods were employed.Results53 renal allografts were transplanted to 51 biopsy‐proven IgA N patients: 12 were cadaveric (CAD) grafts, 3 HLA‐mismatched living related donor (LRD) kidneys, 29 one haplotype‐matched LRD and 9 HLA‐identical LRD organs. Five‐year actuarial graft survival was 100% in HLA‐ identical LRD, 88% in one haplotype‐matched LRD, and 74% in CAD grafts. All three HLA‐mismatched LRD kidneys were functioning up to 1.6 yr (longest follow‐up). Only one patient died after acute rejection of the CAD graft. There were 3 early graft losses from acute rejection and 4 late losses. IgA N recurred in 26% of allografts and led to significant loss of graft function in 10 of the 14 patients (71%) over a long period of observation. Three of four late graft losses were in patients with recurrent IgA N. Recurrence was not related to the type of graft, i.e. CAD vs. LRD, nor to the extent of HLA‐matching in LRD transplantation.ConclusionRenal transplantation in patients with IgA N has excellent patient and graft survival. There is a high rate of recurrence of the primary glomerulopathy in the renal allograft, and this event is by no means inconsequential. Loss of renal function and even graft loss occur over prolonged periods of time. There is no disadvantage getting a well matched LRD in regard to incidence of recurrent IgA N. Thus, we encourage LRD transplantation in IgA N.

We examined the value of thallium‐201 myocardial perfusion scintigraphy in noninvasive assessment of cardiac risk in 36 insulin‐dependent (type 1) diabetic patients being evaluated for pancreas or combined pancreas/kidney transplantation. An extensive cardiovascular evaluation including electrocardiogram was performed in all patients, and most patients were also evaluated by two‐dimensional and Doppler echocardiography. Exercise thallium studies were performed in 31 patients. Five patients were unable to exercise and underwent dipyridamole‐thallium study. The thallium images were abnormal in 12 patients, 10 of whom underwent coronary arteriography. Significant coronary artery disease was found in 7 of these patients. Nineteen patients underwent pancreatic (3 patients) or pancreato‐renal (16) transplantation without any occurrence of cardiac death or nonfatal myocardial infarction peri‐operatively or on follow‐up ranging from 7 months to 21 months. In contrast, 3 cardiac events occurred in 12 patients not approved for transplantation, each of whom had an abnormal thallium study exhibiting significant ischemia. Resting left ventricular global and regional function was not helpful in determining perioperative risk. Thus, thallium‐201 myocardial perfusion scintigraphy may be useful in identifying diabetic patients at low risk for pancreas transplantation and may obviate the need for routine coronary angiography in these patients.

Clinical risk factors for nephropathy were assessed in a population-based study of Rochester, Minnesota, residents with diabetes mellitus initially diagnosed between 1945 and 1969 (incidence cohort). The 1031 Rochester residents with non-insulin-dependent diabetes mellitus (NIDDM) were followed through their complete medical records in the community to 1 January 1982. The prevalence of persistent proteinuria was 8.2% at the diagnosis of NIDDM. Among those initially free of persistent proteinuria, the subsequent incidence was 15.3/1000 person-yr. Twenty years after the diagnosis of diabetes, the cumulative incidence of persistent proteinuria was 24.6%. A proportional hazards model identified the following risk factors for persistent proteinuria in NIDDM: elevated initial fasting blood glucose (P < .01); older age at onset of diabetes (P < .01); male gender (P = .05); and presence of macrovascular disease (P = .05), diabetic retinopathy (P = .05), or glycosuria (P = .07) at the diagnosis of diabetes. Separate analyses controlling for attained age indicated no association between duration of NIDDM and the incidence of persistent proteinuria. Stratified analysis of the two most significant risk factors (fasting blood glucose and age) indicated that hyperglycemia was a stronger risk factor for proteinuria in younger diabetic subjects, perhaps because of a competing risk of death in the elderly diabetic patient. In contrast to a recently described decreasing secular trend of proteinuria in Danish insulin-dependent diabetes mellitus patients, there was no decrease over the past 40 yr in proteinuria risk in this NIDDM incidence cohort.

Simultaneous determinations of serum potassium and sodium, blood pH, blood pressure, and 12-lead electrocardiograms were obtained in hyperkalemic patients with chronic renal failure. Statistical investigation of the data showed a high correlation between serum potassium levels and ventricular repolarization abnormalities. "Mean intracellular potassium concentration" derived from total body potassium and total body water values was not accurate enough to show significant correlations to ECG changes and did not improve on the already significant correlations with serum potassium levels. Equations are presented which would permit the estimation of serum potassium levels (in a narrow range) from electrocardiographic findings in patients with chronic renal failure and suspected hyperkalemia.