The appearance of cartilage used in deep inferior epigastric perforator breast reconstruction surgery as a calcified mass on CT scan.

This paper describes an unusual radiological appearance of implanted cartilage on CT scan in a patient who had recently undergone deep inferior epigastric perforator (DIEP) breast reconstruction surgery following a mastectomy for ductal carcinoma in situ. The purpose of this paper is to alert medical practitioners involved with DIEP breast reconstruction surgery, as well as general radiologists, to the possibility of surgically implanted costal cartilage undergoing calcification and then appearing on imaging studies as a malignant process. Information on the patient was gathered from clinical records, imaging reports and pathological samples. A literature search was performed to identify similar cases and the results showed that this occurrence has never before been described and therefore represents an advancement of knowledge about the imaging characteristics of reconstructed breast tissue.

Paradoxical pulmonary embolism secondary to aortocaval fistula: diagnosis by helical CT.

Spontaneous aortocaval fistula is an unusual but well recognized complication of abdominal aortic aneurysm. Reports of aortocaval fistula as the source of pulmonary embolism are rare. We report a case of paradoxical pulmonary embolism secondary to an aortocaval fistula. The abdominal aortic aneurysm and the associated aortocaval fistula were well demonstrated on helical CT, leading to early diagnosis and prompt surgical treatment with good clinical outcome.

Is the emergency readmission rate a valid outcome indicator?

OBJECTIVES: The principal aim was to determine whether the emergency readmission rate varies between medical specialties, and to identify whether differences in emergency readmission rates between hospital trusts can be reduced by standardising for specialty. Possible factors influencing emergency readmission were also investigated, including frequency of previous admission and cause of readmission. DESIGN: Emergency readmission rates were obtained from the Scottish Morbidity Record scheme (SMR1) using record linkage, standardised for age and sex. Rates throughout Scotland were analysed by specialty, and rates for general medicine compared among teaching hospital trusts. Cause of emergency readmission was determined from hospital records in a random sample (177 patients). SETTING: Medical specialties throughout Scotland. SUBJECTS: All patients readmitted as an emergency within 28 days of discharge (October 1990 to September 1994). RESULTS: Emergency readmissions varied markedly between medical specialties, with highest rates in nephrology (24.2%, 95% CI 23.5 to 24.8) and haematology (20.4%, 95% CI 19.9 to 20.9), and the lowest in homeopathy (2.2%, 95% CI 1.6 to 2.7) and metabolic diseases (3.5%, 95% CI 2.4 to 4.5). The largest number of emergency readmissions was in general medicine, accounting for 63% of the total. Restricting emergency readmission rates to general medicine significantly altered previous rates. In the year preceding the emergency readmission, 59% of all patients had been admitted to hospital at least once, and most emergency readmissions (73.3%) resulted from a chronic underlying condition. CONCLUSIONS: Significant variations in emergency readmission rates occurred between medical specialties, suggesting that differences between hospital trusts are influenced by differences in specialties and thus case mix. The majority of emergency readmissions occurred in patients with an underlying chronic condition, and many had a history of multiple previous hospital admissions. The emergency readmission rate is therefore unlikely to be a valid outcome indicator reflecting quality of care until routine data are available for standardisation by case mix.

Twin zygosity testing for medical purposes.

After being poisoned by eating the mushroom species Cortinarius speciosissimus, a twin developed interstitial nephritis with acute renal failure. He received a renal transplant from his living twin brother, who was presumed dizygotic on phenotypic grounds. Fifteen years later, the twins were zygosity tested by DNA "fingerprint analysis" and found to be monozygotic, despite important phenotypic discordances. The recipient has discontinued immunosuppression therapy and remains well after 9 months. We suggest that, for medical and other reasons, zygosity should be determined at birth on all like-sexed twins.

A comparison of 2-D and 3-D FSE imaging in MR of the cervical spine.

The aim of the study was to assess whether a 3-D FSE sequence with real-time multiplanar reconstruction could replace our standard 2-D imaging of the cervical spine. MRI was performed on a GE Vectra 0.5 T system using a quadrature surface neck coil. Signal intensity of CSF, spinal cord, surrounding tissue and background were measured. Contrast to noise ratio and contrast between the different tissues was calculated for the different sequences. A subjective assessment of the various lesions was made. No statistical difference in tissue contrast was found between 2-D and 3-D images when the contrast between cord and CSF, or between cord and marrow was calculated. Contrast between cord and marrow was better on 3-D images. The contrast to noise ratio was better on 2-D images compared with the 3-D images for both cord/CSF and CSF/marrow but there was no difference between the 2-D and 3-D images for cord/marrow. In three patients the lesion was better demonstrated on the 3-D sequence than on the 2-D combination, but only in one of these was the abnormality not visible on the 2-D images; in six patients the 2-D images were considered superior. Although the 3-D sequence reduced overall imaging time we found that at 0.5 T contrast was inadequate, and that lesions were less clearly demonstrated than on the 2-D sequences. We conclude that a single 3-D sequence cannot satisfactorily replace the 2-D combination routinely used at 0.5 T.

Changes in atrial natriuretic peptide and plasma renin activity following changes in right atrial pressure in patients with chronic renal failure.

Since it was first discovered in the early 1980s, the role of atrial natriuretic peptide (ANP) in the control of fluid and electrolyte balance and blood pressure has been extensively studied in both health and disease. We report here a study of ANP and its relationship to corresponding changes in right atrial pressure (RAP) in patients with chronic renal failure (CRF) on haemodialysis compared to healthy controls. Although there was a positive correlation between RAP and ANP in both groups, the changes in ANP following changes in RAP between the two groups were not statistically significant. A unique observation was the response of RAP to changes in posture, with RAP falling significantly as expected in healthy controls in contrast to the exceptional absence of a significant fall in patients with CRF. Healthy controls demonstrated appropriate postural changes in plasma renin activity (PRA) despite marked suppression of PRA levels due to salt loading, in complete contrast to patients with CRF who, despite chronic fluid overload and elevated levels of ANP, continued to have grossly elevated PRA levels that failed to change significantly in response to changes in posture.

Renal tubular responses to low-dose infusion of angiotensin II in type 1 diabetes mellitus; relation to chronic glycaemic control.

Renal responses to low-dose infusion of angiotensin II (ANGII, 1.25 and 2.5 ng.kg-1 min-1) were examined in 15 patients with type 1 diabetes and in 10 control subjects after pretreatment with lithium carbonate (750 mg, 20 mmol). Mean arterial pressure rose during ANGII infusion in both groups. The renal haemodynamic response to angiotensin II was not abnormal in the diabetic patients. Absolute proximal reabsorption of sodium was increased at baseline in the diabetic group, and fell during ANGII. Fractional lithium excretion was reduced in the diabetic patients at baseline (P < 0.05), and the fall in fractional lithium excretion during ANGII was less than in the control group (P = 0.012). In the diabetic group correlations existed between glycated haemoglobin and baseline glomerular filtration rate (P < 0.05), baseline fractional lithium excretion (P = 0.03), and the fall in fractional lithium excretion during angiotensin II infusion (P = 0.013). There was no correlation between glycated haemoglobin and absolute lithium clearance. Some indices of sodium reabsorption by the proximal renal tubule in diabetic patients correlate with prevailing chronic glycaemic control, largely reflecting changes in glomerular filtration rate. Reduced fractional proximal tubular responsiveness to exogenous angiotensin II is consistent with a role for endogenous angiotensin II as one mediator of increased tubular reabsorption of sodium in type 1 diabetes, but the data does not exclude alternative mechanisms.

Supraventricular tachycardia, right atrial pressure, atrial natriuretic peptide and polyuria--a necessary sequence?

The release of atrial natriuretic peptide (ANP) may be stimulated by tachycardia and the evidence from human studies suggests that this is mediated by a rise in atrial pressure. However, animal experiments suggest that tachycardia can by itself increase ANP levels without increasing right atrial pressure (RAP). We report here the case of a healthy volunteer who had supraventricular tachycardia (SVT) whilst participating in a study evaluating the relationship between changes in RAP and changes in ANP. The ANP levels rose following the SVT but there was no rise in RAP, suggesting that heart rate can modulate ANP levels without changes in RAP as has been shown in animal experiments.

Antinatriuretic action of insulin is preserved after angiotensin I converting enzyme inhibition in normal man.

To examine the potential role for intrarenal angiotensin II in mediating the antinatriuretic action of insulin, seven normal males were studied on three occasions, twice during euglycaemic hyperinsulinaemia (40 mU.m-2.min-1) after double-blind treatment for 1 week with placebo and the converting enzyme inhibitor perindopril, and on a time control day. Lithium carbonate 250 mg was given before each study as an indirect marker of tubular sodium handling. Renal haemodynamics did not change during hyperinsulinaemia. Insulin infusion reduced both the absolute and fractional urinary excretion rates of sodium (P < 0.001) and potassium (P < 0.001); these effects of insulin were not altered after converting enzyme inhibition. Lithium clearance did not change during insulin infusion on either day. The antinatriuretic effect of hyperinsulinaemia is mediated at a tubular site distal to the proximal tubule. The data does not support the hypothesis that intrarenal generation of angiotensin II plays a part in this action of insulin.

Urinary dopamine response to angiotensin II is not abnormal in type 1 (insulin-dependent) diabetes mellitus.

To examine the interaction between angiotensin II (ANGII) and dopamine in type 1 diabetes mellitus, urinary dopamine excretion was examined during ANGII infusion in 15 diabetic patients and 10 control subjects after pretreatment with lithium 750 mg and placebo. The antinatriuretic response and the urinary dopamine response to ANGII did not differ within or between the two groups on each study day. No correlation was observed between the decrements in urinary sodium excretion and urinary dopamine output during ANGII infusion in either group. The effect of insulin on urinary dopamine excretion was studied separately in seven non-diabetic subjects; sodium and potassium retention occurred during a hyperinsulinaemic euglycaemic clamp, but urinary dopamine did not change. The data suggest that the relationship between urinary sodium excretion and tubular dopamine synthesis remains normal in early type 1 diabetes mellitus both at baseline and during the antinatriuresis induced by angiotensin II. The cause of the reduction in urinary dopamine during ANGII infusion is unclear, but is probably not mediated directly by changes in proximal tubular sodium transport.

Oral herpes simplex virus type 1 infection following cadaveric renal transplantation in a young type 1 diabetic female. The role of acyclovir: a case report.

Oral infection with Herpes Simplex Virus (HSV) is a frequent and well documented complication in immunosuppressed individuals including patients on immunosuppressive medication. We report the development of severe oral infection with HSV type 1 in a 34 year old woman with type 1 diabetes mellitus and end stage renal disease (ESRD) following cadaveric renal transplantation at the Western General Hospital, Edinburgh. The role of acyclovir in therapy and chemoprophylaxis is discussed.

Lithium pretreatment affects renal and systemic responses to angiotensin II infusion in normal man.

1. Renal and systemic responses to infusion of angiotensin II (1.25 and 2.5 ng min-1 kg-1 body weight) were examined in ten normal males 12 h after single doses of 750 mg of lithium carbonate, 250 mg of lithium carbonate (n = 6) or placebo. 2. Baseline mean arterial pressure [mean (SEM)] was higher after 750 mg of lithium [93.1 (1.7) versus 89.5 (1.9 mmHg, P = 0.014], and the subsequent rise in blood pressure during angiotensin II infusion was lower [8.2 (1.8) versus 12.2 (2.4) mmHg, P less than 0.02]. 3. Lithium at a dose of 750 mg increased overnight urinary sodium excretion before the study. The fall in fractional sodium excretion during angiotensin II infusion was reduced after pretreatment with 750 mg of lithium [750 mg of lithium, 2.73 (0.24) to 1.34 (0.08)%; placebo, 2.69 (0.26) to 1.01 (0.11)%; P = 0.02]. The increases in effective filtration fraction [750 mg of lithium, 5.4 (1.0)%; placebo, 8.6 (0.7)%; P less than 0.05] and total effective renal vascular resistance [750 mg of lithium, 3700 (390) dyn s cm-5; placebo 5100 (460) dyn s cm-5; P = 0.03] during angiotensin II infusion were also attenuated after 750 mg of lithium. Responses after 250 mg of lithium did not differ from those after placebo. 4. The fall in plasma renin activity and the increase in plasma aldosterone concentration during angiotensin II infusion were similar on each study day. 5. Renal responses to exogenous angiotensin II are altered after pretreatment with a 750 mg dose of lithium in normal man. This dose of lithium is not an inert marker of sodium handling.

Changes in renal function during acute insulin-induced hypoglycaemia in patients with type 1 diabetes.

The effect of acute hypoglycaemia on renal function was examined in eight male patients with Type 1 diabetes who had normal urinary albumin excretion. Insulin was given as a bolus intravenous injection (0.125 U kg-1) and plasma glucose fell to a nadir of 1.6 (SE 0.2) mmol l-1, with all patients experiencing an acute autonomic reaction. Renal plasma flow fell from 674 (106) to 540 (198) ml min-1 during hypoglycaemia (p less than 0.01) and returned to 655 (181) ml min-1 (NS vs baseline). Glomerular filtration rate (GFR) declined from 143 (23) to 110 (36) ml min-1 during hypoglycaemia (p less than 0.02), rising to 150 (44) ml min-1 in the recovery period (NS vs baseline). The urinary flow rate and urinary albumin excretion rate both fell significantly in response to hypoglycaemia (10.6 (1.2) to 4.7 (1.1) ml min-1; p less than 0.002, and 46.2 (10.6) to 26.0 (10.5) micrograms min-1, respectively). Urinary dopamine excretion also declined, from 322 (37) to 211 (29) mumol min-1 (p less than 0.005) but sodium excretion was unchanged. Plasma adrenaline concentration (0.2 (0.03) to 1.7 (0.4) nmol l-1; p less than 0.01) and plasma renin activity (0.49 (0.13) to 1.08 (0.17) ng-Ang 1 l-1 h-1; p less than 0.01) increased during hypoglycaemia, but changes in plasma noradrenaline and angiotensin II levels did not attain significance. These acute changes in renal function, observed during hypoglycaemia in diabetic patients, may result from direct stimulation of the efferent sympathetic nerves to the kidney, complemented by the hormonal changes induced by hypoglycaemia.

Renal responses to angiotensin II infusion in early type 1 (insulin-dependent) diabetes.

The renal response to infusion of sub-pressor doses of angiotension II was examined in nine euglycaemic Type 1 (insulin-dependent) diabetic patients with diabetes of short duration and nine non-diabetic control subjects. Plasma concentrations of angiotensin II and of free insulin were similar in both groups at baseline and during angiotensin II infusion. Glomerular filtration rate (Inutest clearance) fell to a similar extent during angiotensin II infusion in both groups (diabetic 116(SE 5) to 102(5) ml min-1 1.73-m-2; control 113(6) to 100(5) ml min-1 1.73-m-2). There was a large dose-dependent fall in effective renal plasma flow (p-aminohippurate clearance) during angiotensin II infusion which was of similar magnitude in both groups (diabetic; 694(46) to 521(21) ml min-1 1.73-m-2; control 665(41) to 498(30) ml min-1 1.73-m-2). The absolute and the fractional rates of urinary excretion of sodium were both lower in the diabetic group throughout the study, but there was a comparable antinatriuretic response to angiotensin II. Thus, the renal haemodynamic response to angiotensin II infusion is normal in early well-controlled Type 1 diabetes. Differences were found in the renal handling of sodium, which could not be related to altered renal tubular responses to angiotensin II or to peripheral hyperinsulinaemia.

Successful treatment of Prototheca peritonitis complicating continuous ambulatory peritoneal dialysis.

We describe the second reported case of peritonitis caused by the alga Prototheca wickerhamii in a patient on continuous ambulatory peritoneal dialysis (CAPD). This organism, which grows slowly on agar media, is recognised as a race cause of other infections. The condition is clinically similar to cases of fungal peritonitis, but there are important differences, particularly when choosing the best treatment.

Oral carbidopa has no effect on the renal response to angiotensin II in normal man.

1. The effect of inhibition of intrarenal dopamine synthesis by carbidopa on the renal response to angiotensin II infusion was studied in six healthy salt-loaded volunteers. 2. Subjects received an infusion of angiotensin II at two doses (0.5 and 1.0 ng min-1 kg-1) on two occasions. Before one study they took a single dose of carbidopa (100 mg) by mouth. 3. The plasma concentrations of angiotensin II produced by the infusion were similar on both study days. Angiotensin II infusion reduced urinary dopamine excretion on the control day. Urinary dopamine excretion was undetectable at all times after carbidopa, but carbidopa did not change the basal excretion rate of sodium. Despite inhibition of renal dopamine synthesis, the reductions in both absolute and fractional sodium excretion during the angiotensin II infusion were not different from those seen in the control study. 4. The reductions in glomerular filtration rate and effective renal plasma flow which occurred during angiotensin II infusion were not modified by pretreatment with carbidopa. 5. The renal response to angiotensin II is not modulated either wholly or in part by endogenous intrarenal dopamine levels. The fall in urinary dopamine excretion which occurs during angiotensin II infusion is consistent with a modulatory role for tubular reabsorptive capacity in the regulation of proximal tubular dopamine synthesis.

Effects of atrial natriuretic peptide (99-126) in chronic renal disease in man.

Plasma concentrations of human atrial natriuretic peptide (99-126) are elevated in patients with end-stage chronic renal failure and on haemodialysis. Plasma atrial natriuretic peptide (ANP) concentrations change with extracellular fluid volume, suggesting that ANP continues to have a role in chronic renal failure. We have studied the effects of an infusion (5 pmol/kg per min) in subjects with chronic renal failure (CCr) less than 30 ml/min per 1.73 m2). Glomerular filtration rate and effective renal plasma flow increased by 23% (P less than 0.01) and 27% (P less than 0.01) respectively and sodium excretion more than doubled. Systolic and diastolic blood pressures decreased by 14 (SD 1.6) and 6 (SD 0.8) mmHg respectively (P less than 0.001), and plasma renin activity declined (P less than 0.01). Plasma ANP concentrations were elevated compared to normal subjects and reached a peak of 224 (SD 87) pmol/l at the end of the infusion. Plasma half-life was 4.8 (SD 2.7) min. Plasma concentrations are elevated in chronic renal failure and ANP may play a physiological role in controlling extracellular fluid volume and blood pressure.