Renal vein oxygen saturation in renal artery stenosis.

Renal vein oxygen-saturation was measured in 56 patients with arterial hypertension and unilateral stenosis or occlusion of the renal artery. Oxygen-saturation in blood from the ischaemic kidney (84.4%, range 73-93%) was significantly higher than that from the 'normal' contralateral kidney (81.2%, range 70-90%, P less than 0.001). In only six patients, the ischaemic kidney revealed a venous oxygen-saturation below the contralateral value (mean difference ischaemic-normal kidney 3.2%, range -6 to 15%). The results indicate that the oxygen uptake in the chronic ischaemic kidney is more decreased than its blood flow. This is probably due to decreased filtration fraction and filtered sodium with subsequent reduction in absolute tubular re-absorption of sodium ions.     

Atubular glomeruli in renal artery stenosis.

The aim of the present study was to investigate and quantitate the structural renal changes developing after stenosis of the renal artery. Twelve kidneys removed at operation from patients with elevated blood pressure due to stenosis of the renal artery were investigated together with three kidneys with renal artery stenosis but no clinical evidence of renovascular hypertension. Eight age-matched autopsy kidneys served as controls. Stereologic methods were used to estimate the volume fractions of different structural parameters, the volume of individual glomeruli, and the structural integrity between the glomerulus and the proximal tubule. In six of the kidneys with renal artery stenosis and in the controls, the total number of nonoccluded glomeruli was estimated. Immunohistochemical staining for epithelial membrane antigen, Tamm-Horsfall protein and lectin Arachis hypogaea was performed in order to determine whether the atrophic tubules in renal artery stenosis were of proximal or distal origin. The results showed that the volume fractions of both proximal and distal tubules had decreased in renal artery stenosis, whereas the volume fractions of the glomerular tufts and interstitium increased. Immunohistochemical staining indicated, however, that more distal than proximal tubules were preserved, although atrophic. In the kidneys with artery stenosis, very few glomeruli were seen connected to a normal proximal tubule; in 52% of the glomeruli Bowman's capsule did not open toward a tubule and 40% were connected to an atrophic tubule. The mean glomerular volume (uncorrected for shrinkage) of 1.5.10(6) microns3 in the kidneys with artery stenosis was significantly decreased compared with the 2.9.10(6) microns3 in the controls. The mean glomerular number was normal in the kidneys with artery stenosis. The study shows that despite the absence or severe atrophy of the tubules, the glomeruli are not destroyed but only smaller. More proximal than distal tubules are destroyed by the ischemic process.     

The hyponatremic hypertensive syndrome in renal artery stenosis: an infrequent cause of hyponatremia

The hyponatremic hypertensive syndrome is a rare but serious complication of reno-vascular disease. The syndrome is characterized by hypertension and profound natriuresis, leading to body sodium and water depletion. Hypertension is typically refractory to treatment. We report an 82-year-old patient with this syndrome and describe the results of an audit of the clinical records of patients admitted to a teaching hospital over a two-year period with confirmed renal artery stenosis and hyponatremia. The syndrome should be suspected in patients in whom severe hypertension is associated with hyponatremia without other apparent cause, especially in the presence of reno-vascular disease.     

Time course of the enhanced blood pressure response to reinduction of renal artery stenosis in unclipped renal hypertensive rats

Moderate or severe hypertension was induced in rats by application of a clip 0.25 or 0.20 mm internal diameter) to the left renal artery leaving the contralateral kidney intact. Removal of the clip 6, 13 or 24 days after the induction of the hypertension was followed by a rapid decrease in blood pressure. A near normotensive level was reached after 2–6 h. Reapplication of the clip to the unclipped renal artery after 1 day caused an enhanced blood pressure response. The preoperative hypertensive levels were reached within 2 h. This enhanced response was related to the level of blood pressure before the removal of the clip. Lengthening the interval between removal and reapplication of the clip gradually reduced the enhanced response of blood pressure, which had disappeared 8 days after the removal of the clip. Reapplication of the clip to the contralateral renal artery was not followed by an enhanced response in rats with previous moderate or severe hypertension.     

Hemodynamic adjustments during free-operant avoidance in dogs with unilateral renal artery stenosis.

To examine blood pressure (BP) and heart rate (HR) during avoidance performance in animals with renal artery stenosis, 10 dogs were prepared with arterial catheters, and subsequently underwent habituation to the experimental apparatus. Following this, 6 of the dogs received ligation of the left renal artery to reduce luminal dia. 50–80%, and habituation was repeated in all dogs. After training on a free-operant avoidance task, the animals were exposed to 5 daily 60 min avoidance sessions consisting of alternating 5 min periods of non-avoidance and avoidance. On 2 days, the dogs received either propranolol (0.3 mg/kg) or phenoxybenzamine (1.0 mg/kg) intra-arterially during the second nonavoidance period. While stenosis of the renal artery was effective in increasing diastolic BP during the second habituation exposure, a permanent BP elevation was not observed. These animals displayed similar pressor responses but larger HR increases than controls during the first and final avoidance periods. Drug effects were minimal. The results suggest that an exaggerated tachycardia may characterize the hemodynamic adjustment to environmental challenges in animals with unilateral renal artery stenosis, as it does in some hypertensive patients.     

Renal artery changes in patients with primary renal cell carcinoma

Arterial fibromuscular dysplasia (FMD) is a noninflammatory, nonatherosclerotic, occlusive condition of the systemic arteries, most frequently affecting renal arteries. Renal cell carcinoma (RCC) might be associated with arterial hypertension; however, there are no data in the literature regarding the relationship between RCC and associated renal artery changes. We analyzed a consecutive series of 57 (35 male and 22 female) patients aging from 35 to 79 years (mean 58.9 years) who underwent nephrectomy due to RCC in the year 2003. The patients had RCC measuring from 2 to 16 cm (mean 7.1 cm). Specimens were routinely fixed, embedded in paraffin, cut, and stained with hematoxylin and eosin, Mallory trichrome method, and orcein. Renal arteries of 26 patients (20 male, 6 female) showed no changes. In these patients, RCC measured 2.5–11 cm in largest diameter (mean 6.6 cm). In 24 patients (10 male, 14 female), renal arteries showed FMD. RCCs in these patients measured between 2 and 16 cm (mean 8.0 cm). Seven patients had atherosclerotic changes in renal arteries. In this series, FMD was found in a significant proportion of patients with RCC, mainly in women. The cause of such changes and their relationship with RCC and systemic hypertension should be further analyzed. Presented in part at the XXV International Academy of Pathology Congress, Brisbane, Australia, October 10–15, 2004.     

Thorax high resolution computerized tomography findings in asthmatic children with unusual clinical manifestations.

BACKGROUND: It has been consistently observed in high resolution computerized tomography (HRCT) scans that asthmatic patients manifest more abnormalities related to airways remodeling than do normal subjects. OBJECTIVE: To find the underlying abnormalities in the lungs of asthmatic children with unusual manifestations. METHOD: Asthmatic children not responding as expected to inhaled steroid therapy with or without localized permanent or temporary recurrent auscultation findings (rales) were evaluated with chest radiographs and HRCT scans. Bronchoscopy was performed on the ones with localized rales. RESULTS: The sample consisted of 16 asthmatic children (6 girls and 10 boys, mean age = 7.75+/-4.43 years). Chest radiograph abnormality rate was 44% and the thorax HRCT scan abnormality rate was 75% (56% fibrotic retractions, 38% atelectasis, 19% bronchiectasis, and 19% bronchial wall thickening). Two patients with localized permanent rales and with right middle lobe (RML) atelectasis in HRCT scan underwent bronchoscopy which revealed RML syndrome due to mucus plugging in one and lymph node pressure in the other. In one patient with localized temporary recurrent rales and major bronchiectasis in HRCT scan, bronchoscopy revealed bronchitis. The patient with RML syndrome due to mucus plugging required lobectomy. CONCLUSION: We conclude with this experience that thorax HRCT scanning may be a helpful adjunct in the evaluation of an asthmatic children with atypical clinical findings.     

Renal failure and nephrocalcinosis associated with oral sodium phosphate bowel cleansing: clinical patterns and renal biopsy findings

Acute renal failure (ARF) is rarely reported after bowel preparation with sodium phosphate. We report a patient with mild Crohn disease (in remission), without history of renal disease, and with normal baseline renal function, who developed ARF 14 days after bowel preparation for colonoscopy with oral sodium phosphate. A renal biopsy showed multifocal calcium phosphate deposition in the renal tubules against a background of diffuse chronic tubulointerstitial injury. Review of the literature suggested 2 distinct patterns of ARF in the context of sodium phosphate bowel cleansing. One pattern is characterized by ARF, which develops a few hours or days after sodium phosphate administration, as a component of a systemic syndrome associated with severe hyperphosphatemia and hypocalcemia. Correction of these electrolyte abnormalities was frequently associated with rapid recovery of renal function. The cause of ARF in this context was not clear because the favorable outcome negated the need for renal biopsy. In the second pattern, exemplified by the current patient, ARF was identified incidentally. These patients did not have any features of an acute syndrome immediately after sodium phosphate administration and presented much later (usually weeks) with mild, nonspecific symptoms. At the time of presentation, the serum calcium and phosphate levels were normal. The renal biopsies in each of these patients showed nephrocalcinosis as the possible cause of ARF. The renal failure improved at least partially in most of these patients, but persisted in rare cases.     

Fluid volumes and pressor responsiveness in two-kidney rabbits with renal artery stenosis

This study examined body fluid volumes, the pressor responses to norepinephrine (NE), and the cardiovascular responses to NE before and during infusion of an angiotensin II (ANG II) antagonist in two-kidney rabbits with unilateral renal artery stenosis (RAS) of 3 and 30 day duration. Three separate experiments were performed. In the first experiment, plasma volume, extracellular fluid volume, and total body water were measured by the distribution volumes of radioiodinated serum albumin, 35SO4, and tritiated water, respectively. No differences were seen for any of these volumes between the 3- or 30-day RAS rabbits and their controls. In the second experiment, pressor responses to infusions of several doses of NE were examined; rabbits with 3- and 30-day RAS had exaggerated pressor responses to all doses of NE when compared with the control rabbits. In the third experiment, infusion of NE at 800 ng.min-1.kg body wt-1 resulted in more pronounced increases in mean arterial pressure and total peripheral resistance (TPR) in the 3- and 30-day RAS rabbits than in the controls; after infusion of [Sar1-Ile8] ANG II the increases in mean arterial pressure and TPR during NE infusion were blunted and were of the same magnitude as in the control group. In all experiments the 30-day RAS rabbits were hypertensive, whereas the 3-day RAS rabbits were normotensive; also, plasma renin activity (PRA) values were normal in both the 3- and 30-day RAS groups. These studies demonstrated that increases in body fluid volumes are not necessary for pressor and vascular hyperresponsiveness probably is mediated by ANG II, despite normal PRA values.     

Mucolipidosis II. The clinical, radiological and biochemical features in three cases

We report on the clinical, radiological and biochemical features of mucolipidosis II in three infants. One with subtle phenotypical findings died at 2 weeks of age without a specific diagnosis. A sibling who died at 2 years of age and another infant, presently 3.5 years of age manifest all the characteristic features of mucolipidosis II: extreme psychomotor delay and failure to thrive, coarse facial features, gingival hyperplasia, joint stiffness, inguinal hernia and skin induration. The corneae were normal and there was no mucopolysacchariduria. Radiologically, these infants show changes which are characteristic but not specific for mucolipidosis II. Cytologically, skin fibroblasts from these patients demonstrate the lysosomal inclusions typical of I-Cell Disease. Biochemically, cultured skin fibroblasts show deficient activity of arylsulphatase A and B and hexosaminidase A and B. These acid hydrolases were increased markedly in plasma and in the culture medium of the skin fibroblasts.     

Anti-adrenal cellular hypersensitivity in Addison's disease. II. Correlation with clinical and serological findings

Previous observations suggesting the existence in idiopathic Addison's disease of a state of anti-adrenal cellular hypersensitivity is extended to a larger material comprising thirty cases of idiopathic Addison's disease and seven cases of tuberculous Addison's disease. The specific anti-adrenal humoral and cellular hypersensitivity is evaluated by means of the indirect immunofluorescence technique and the leucocyte migration test, respectively.

Anti-adrenal cellular hypersensitivity was demonstrable in 46% of patients with idiopathic Addison's disease but in no case of Addison's disease of unquestionable tuberculous origin. Anti-adrenal cellular hypersensitivity could be demonstrated more frequently in males (eight out of eleven) than in females (six out of nineteen).

Anti-adrenal humoral hypersensitivity, i.e. occurrence of circulating anti-adrenal antibody, could be demonstrated in 73% of the patients with idiopathic Addison's disease. Humoral and/or cellular anti-adrenal hypersensitivity was found in 90% of the patients with idiopathic Addison's disease.

No correlation was observed between the occurrence of anti-adrenal cellular hypersensitivity, and the duration of clinical illness and the presence or absence of anti-adrenal antibody.

In two patients with diabetes mellitus humoral as well as cellular anti-adrenal hypersensitivity was demonstrated, although they had no clinical signs of Addison's disease.

     

Histopathological and clinical findings in renal transplants with Banff type II and III acute cellular rejection without tubulointerstitial infiltrates

According to the Banff guidelines for renal transplants, pure endothelialitis without any tubulointerstitial infiltrates (with the Banff components v?≥?1, i0, t0) has to be called acute cellular rejection (ACR). The pathophysiology of this rare lesion abbreviated as v_only is currently unclear, as well as its clinical, serological, and prognostic implications. Therefore, we conducted this retrospective comparative study. We compared all 23 biopsies with v_only from Hannover Medical School between 2003 and 2010 with 23 matched biopsies with the Banff components v?≥?1, i?≥?1, and t?≥?1 (v_plus) and 23 biopsies with v0, i0, and t0 (v0i0t0). Serological (available in 10, 11, and 14 patients, respectively), histological, and clinical data were compared. Of all biopsies, 0.4 % had findings of v_only. v_only, v_plus, and v0i0t0 only showed minimal differences in the Banff components apart from the cohort-defining components. Endothelialitis in v_only more frequently involved the arcuate arteries than the smaller preglomerular vessels compared to v_plus and vice versa. Combining histopathological data and serological data, v_only more frequently showed criteria for acute humoral rejection than v0i0t0 (albeit not persistent after the Bonferroni–Holm correction in pairwise comparisons), while there was no difference between v_only and v_plus. No difference could be demonstrated regarding clinical presentation at biopsy or outcome. Our results show minimal differences regarding clinical presentation, outcome, and histological features between v_only and v_plus. Patients with v_only should be thoroughly investigated for evidence of acute humoral rejection.     

Evoked potential study and radiological findings in patients with systemic lupus erythematosus.

We performed clinical, radiological (MRI) and neurophysiological (NCV, SEPs, and BAEPs) investigations in 36 unselected patients affected by Systemic Lupus Erythematosus (SLE). Fifteen patients (42%) presented clear neurological events and were considered as definite neuropsychiatric lupus (NPLE); 21 (58%) presented minor subjective complaints or no neurological problems referable to SLE and were considered as no-NPLE. Twenty-three patients (64%) showed neurophysiological abnormalities: 21 (58%) presented central abnormal neurophysiological measurements (including SEP and BAEP values), while 17 (47%) has slowed peripheral nerve conduction. Twenty-six out of 36 patients executed brain MRI examination. High intensity spots (HIS) in deep or subcortical white matter were the most common abnormalities and were present in 19 of the 26 patients (73%). We found that the incidence of neurophysiological and radiological abnormalities did not significantly differ in neurologically symptomatic and asymptomatic patients. Central nervous system impairment evidenced by abnormal N13-20 interpeak intervals (p = 0.05) and HIS (p = 0.01) findings was significantly associated with the presence of cutaneous vasculitis; while peripheral nerve involvement was significantly more frequent in patients with renal failure (p = 0.006).