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N Mittman

Publications and source records attributed to N Mittman.

30 records · Page 2Linked to original sources
PubMed1990

The impact of CAPD treatment on lipid metabolism and cardiovascular risk.

The metabolism of lipids in CAPD has not been fully elucidated. To further clarify the behavior of dyslipidemia in this setting we followed the values of total cholesterol (TC), HDL-cholesterol (HDL-C) and apolipoprotein (apo) parameters over time (12-24 months) in 40 patients and correlated these values and their ratios with clinical (age, gender, race, weight, diabetes, etc.) and biochemical (multiphastic screen) information. Mean HDL-C was lower in men (p less than 0.04), in whites, (p less than 0.03) and in diabetic patients (p less than 0.05), but there were no group differences for mean total cholesterol, mean apolipoprotein values, the atherogenic risk ratio TC/HDL-C, or the anti-atherogenic ratio apo A-I/apo B. Total months on CAPD was found to correlate positively with TC/HDL-C (p less than 0.05), an atherogenic risk factor, and to correlate negatively with HDL-C (p less than 0.02), an anti-atherogenic index. There was also a negative correlation with another anti-atherogenic index, apo A-I/apo B, which did not reach statistical significance (r = -0.41, p = NS). Counterbalancing this apparently increased atherogenic risk is the stability of individual parameters for each patient over time in this study. In fact, the good news appears to be that TC, HDL-C, apolipoproteins and the risk ratios TC/HDL-C and apo A-I/apo B all remained stable over 12-24 months (p = NS by paired t-test for all). Thus, we find no evidence for worsening of the uremic dyslipidemia over time with CAPD treatment.

Apolipoproteins↗
PubMed1989

Cholesterol and lipid disturbances in renal disease: the natural history of uremic dyslipidemia and the impact of hemodialysis and continuous ambulatory peritoneal dialysis.

Lipid abnormalities have been postulated to contribute to renal insufficiency by a mechanism that is analogous to atherogenesis. The majority of patients treated for chronic renal failure die of cardiovascular complications. Lipid abnormalities in this group are thought to contribute to this high mortality. Proving a causal association between dyslipidemia and accelerated atherosclerosis in the end-stage renal disease population has been confounded by the presence of other pro-atherogenic conditions in this population. The current study compiles the lipid data we have accumulated from our renal population for the years 1987 to 1989. The report is divided into three main parts: The first is a survey of lipid levels and atherogenicity indicators in groups with different types of renal disease or modalities of treatment. The second is a multivariate analysis of the relationship of clinical and biochemical variables (and their interactions) to the serum lipid and apolipoprotein levels and their ratios and their change over time in a large dialysis population. In the third study, we quantitate the peritoneal clearances of apolipoproteins A-I and B in patients undergoing continuous ambulatory peritoneal dialysis and assess the relationship of these clearances to serum lipid and lipoprotein levels and risk ratios.

Apolipoproteins A↗
PubMed1985

Salicylate nephropathy in the Gunn rat: potential role of prostaglandins.

We examined the potential role of prostaglandins in the development of analgesic nephropathy in the Gunn strain of rat. The homozygous Gunn rats have unconjugated hyperbilirubinemia due to the absence of glucuronyl transferase, leading to marked bilirubin deposition in renal medulla and papilla. These rats are also highly susceptible to develop papillary necrosis with analgesic administration. We used homozygous (jj) and phenotypically normal heterozygous (jJ) animals. Four groups of rats (n = 7) were studied: jj and jJ rats treated either with aspirin 300 mg/kg every other day or sham-treated. After one week, slices of cortex, outer and inner medulla from one kidney were incubated in buffer and prostaglandin synthesis was determined by radioimmunoassay. The other kidney was examined histologically. A marked corticomedullary gradient of prostaglandin synthesis was observed in all groups. PGE2 synthesis was significantly higher in outer medulla, but not cortex or inner medulla, of jj (38 +/- 6 ng/mg prot) than jJ rats (15 +/- 3) (p less than 0.01). Aspirin treatment reduced PGE2 synthesis in all regions, but outer medullary PGE2 remained higher in jj (18 +/- 3) than jJ rats (9 +/- 2) (p less than 0.05). PGF2 alpha was also significantly higher in the outer medulla of jj rats with and without aspirin administration (p less than 0.05). The changes in renal prostaglandin synthesis were accompanied by evidence of renal damage in aspirin-treated jj but not jJ rats as evidenced by: increased incidence and severity of hematuria (p less than 0.01); increased serum creatinine (p less than 0.05); and increase in outer medullary histopathologic lesions (p less than 0.005 compared to either sham-treated jj or aspirin-treated jJ). These results suggest that enhanced prostaglandin synthesis contributes to maintenance of renal function and morphological integrity, and that inhibition of prostaglandin synthesis may lead to pathological renal medullary lesions and deterioration of renal function.

Animals↗
PubMed1985

The changing spectrum of heroin-associated nephropathy.

Thirty-five renal biopsies were performed on heroin abusers at our institution between January 1977 and June 1983 as part of the evaluation of unexplained heavy proteinuria. Twenty-eight patients (80%) had histopathologic diagnoses of either focal segmental glomerulosclerosis or renal amyloidosis. Patients having a diagnosis of renal amyloidosis were older (P = 0.025), had a longer history of heroin abuse (P = 0.05), and 13/14 demonstrated clear evidence of chronic subcutaneous suppurative lesions. The remaining seven patients demonstrated a spectrum of disease similar to that seen in the nonaddicted population. We compared the clinical and biopsy characteristics of patients evaluated between 1977 and 1980 with those seen between 1981 and 1983. The relative incidences of renal amyloidosis and focal glomerulosclerosis changed significantly (P = 0.025). Whereas 29% of patients in the early series had renal amyloidosis and 57% had focal glomerulosclerosis, the relative incidences in the later series were 48% and 29%, respectively. The development of renal amyloidosis in our patients appears to be related to a longer duration of heroin abuse with increased incidence of subcutaneous injection of the narcotic. Chronic, suppurative skin ulcerations tend to occur at the site of injection, resulting in a persistent acute-phase inflammatory state important for the initiation and potentiation of secondary amyloidosis.

Adult↗
PubMed1985

Safety and efficacy of guanabenz in hypertensive patients with moderate renal insufficiency.

Eight hypertensive patients with moderate renal insufficiency were treated with gradually increasing oral doses of guanabenz acetate to a maximum dose of 8 mg BID. Patients' medications were titrated over 8 weeks. Once blood pressure control was achieved (seated diastolic blood pressure, 90 mmHg, or decrease of 10 mmHg from baseline values), drug dosages were maintained for up to a 12-week total treatment phase. Patients had significant reductions of blood pressure during treatment with guanabenz as compared to that during pretreatment levels. No changes in body weight or creatinine clearance were evident, as compared to baseline values. Our data suggest that guanabenz, in relatively small doses, can be used as safe and effective monotherapy of essential hypertension in patients with moderate renal insufficiency.

Blood Urea Nitrogen↗
PubMed1983

Rhodotorula rubra peritonitis in patients undergoing continuous ambulatory peritoneal dialysis.

Although still uncommon, fungal peritonitis is being reported with increasing frequency in patients with renal failure who are undergoing long-term peritoneal dialysis. Although most cases have involved Candida albicans, other opportunistic pathogens have been reported as well. Recently, three patients were seen with serious peritoneal infections due to Rhodotorula rubra, a "nonpathogenic" fungus. In two patients, peritoneal fibrosis made further peritoneal dialysis impossible. The third patient died from complications of peritonitis. Environmental cultures revealed a possible common-source outbreak. Literature review reveals that infection due to this organism is most unusual and occurs only in the hospital setting in patients with serious compromise of host defenses.

Adolescent↗
PubMedDate not supplied

Infectious diseases of the thyroid gland.

Clinical and laboratory characteristics of 224 patients with thyroidal infection reported since 1900 are reviewed. Much of the prior literature on this subject has assumed that most instances of thyroiditis are infectious and that all lymphomatous thyroiditis is tuberculous. Similarly, thyroiditis occurring with syphilis was often equated with treponemal invasion of the gland. Acute bacterial thyroiditis is rapid in onset and more likely than tuberculous infection to produce fever, pain, and tenderness. Suppurative and mycobacterial infections are most common among women with preexisting thyroid disorders. Mortality due to infectious thyroiditis is lower in cases covered by this review than has been previously reported. Gummatous and fungal infections of the thyroid are generally diagnosed only at biopsy or necropsy. Frequent thyroidal involvement in disseminated aspergillosis warrants careful investigation of the gland in patients with this infection. Echinococcosis of the thyroid is a chronic process that is generally diagnosed only following excision.

Acute Disease↗
PubMedDate not supplied

Fall of cholesterol with time on dialysis: impact on atherogenicity.

The majority of patients treated for chronic renal failure die from cardiovascular complications. Lipid abnormalities in this group are thought to contribute to this high mortality. The authors have shown that hemodialysis patients with longer months on dialysis tend to have lower total cholesterol (TC) levels. This study extends data to examine lipid disturbances in 53 continuous ambulatory peritoneal dialysis (CAPD) and 126 hemodialysis patients using multivariate analysis. Longitudinal values after 9-10 months were measured in 16 CAPD patients and 52 hemodialysis patients. Analysis of covariance for all patients demonstrated an inverse correlation of TC (p = 0.003), high-density lipoprotein (HDL) cholesterol (p = 0.01), and apolipoprotein A-I levels (p less than 0.02) with months on dialysis. In addition, the TC level was higher in women (p less than 0.001) and CAPD patients (p less than 0.001), and correlated with age (p = 0.02) and albumin (p less than 0.001). HDL cholesterol was higher in blacks (p less than 0.001) but was not affected by gender, dialysis modality, age, or albumin. Diabetic status, serum parathyroid hormone, and blood pressure were not significant variables for TC or HDL-C. The atherogenic risk indicators, TC/HDL cholesterol (p less than 0.001) and apolipoprotein B (p less than 0.02) were higher in whites than in blacks. Longitudinal study revealed lower TC levels in individual hemodialysis patients (p less than 10(-6) by paired t-test), the fall being greater for patients with fewer total months on dialysis (p less than 0.04, by analysis of covariance). CAPD patients had no change in TC by paired t-test.(ABSTRACT TRUNCATED AT 250 WORDS)

Apolipoproteins↗
PubMedDate not supplied

Longitudinal survey of apolipoproteins and atherogenic risk in hemodialysis and continuous ambulatory peritoneal dialysis patients.

Total cholesterol (TC) and HDL-cholesterol (HDL-C) have been studied in dialysis patients, but a systematic study of apolipoprotein (apo) A-I, apo B, and the anti-atherogenic risk ratio, apo A-I/apo B, over time has not been done. We report lipid and apo values over 12-14 months in 55 hemodialysis (HD) and 40 continuous ambulatory peritoneal dialysis (CAPD) patients. For HD patients, mean TC fell, but not significantly, and HDL-C and TC/HDL-C, an atherogenic risk ratio, did not change over time. Apo A-I/apo B correlated with months on HD (r = 0.30, p less than 0.04) and rose significantly (p less than 0.005) during the study period. Paired t-test analysis by race, gender, and diabetes showed that in nondiabetics, apo A-I rose, apo B fell (p less than 0.05), and apo A-I/apo B improved (p less than 0.002). Similar trends were seen in all subgroups except for diabetics. For CAPD patients, total months of treatment correlated with TC/HDL-C (r = 0.46, p less than 0.05) and with HDL-C (r = -0.53, p less than 0.02), but paired t-test analysis of longitudinal data showed no significant changes in TC, HDL-C, apo A-I, apo B, TC/HDL-C, or apo A-I/apo B. The lipoprotein patterns of all patients who died were not significantly different from those of the surviving patients. Our longitudinal data reveal that lipids, apolipoproteins, and risk ratios remain stable over time on HD and CAPD. In fact, the anti-atherogenic index of apo A-I/apo B improved in HD patients, especially in nondiabetics.

Adult↗
PubMedDate not supplied

Lipids in diabetic and nondiabetic hemodialysis and CAPD patients.

To examine the question of "accelerated atherogenesis" in ESRD patients, the authors conducted a lipid survey among their hemodialysis and CAPD populations and evaluated data relevant to the lipid and diabetic status of these groups. Interestingly, longer duration of hemodialysis in nondiabetic patients was associated with lower cholesterol but not HDL, which may reflect diminished cardiac risk and mortality in the long-term survivors. Diabetic patients showed lower HDL but no cholesterol change with longer duration on hemodialysis. Type I diabetics showed the highest HDL and lowest risk ratio and a strong inverse correlation between PTH and HDL. This study highlights the role of lipids in the atherogenesis of uremia and serves as a baseline for a longitudinal study.

Adult↗