Loredana Colla

Dynamic magnetic resonance imaging in acute pyelonephritis

PurposeThis study was conducted to evaluate the role and clinical impact of dynamic magnetic resonance imaging (MRI) in the diagnosis and follow-up of acute pyelonephritis (APN).Materials and methodsWe retrospectively reviewed 442 consecutive renal MRI examinations (279 diagnostic and 163 follow-up) performed in 285 patients (mean age 42.17 years), 35 of whom were kidney transplant recipients with a clinical suspicion of APN.ResultsMRI showed signal abnormalities suggestive of APN in 125/244 (51.2%) patients with native kidneys. Except for two examinations performed without paramagnetic contrast material, the inflammatory foci appeared as areas of nonenhancement: single in 39/123 cases, multiple in 84/123, unilateral in 60/84 and bilateral in 24/84. Abscesses were present in 40/123 (32.5%) positive cases. During follow-up, we observed complete normalisation of MRI signs in 86/103 patients; 17/103 (16.5%) cases evolved into fibrosis and scarring. In 15/35 (42.8%) patients with transplanted kidney, MRI was positive for APN.ConclusionsRenal MRI is an effective tool for the diagnosis and follow-up of APN both in patients not at risk and those at higher risk, such as those with a transplanted kidney. The high costs of the examination are offset by better treatment planning and early complication detection.RiassuntoObiettivoScopo del presente lavoro è la valutazione del ruolo e dei risvolti clinici dell’impiego della risonanza magnetica (RM) dinamica nella diagnosi e nel follow-up della pielonefrite acuta (PNA).Materiali e metodiÈ stata effettuata un’analisi retrospettiva di 442 esami consecutivi (279 in fase diagnostica e 163 di follow-up) in 285 pazienti (età media 42,17 anni) di cui 35 portatori di trapianto renale con sospetto clinico per PNA.RisultatiIn 125/244 pazienti (51,2%) con reni nativi la RM ha dimostrato alterazioni di segnale suggestive per PNA. Eccetto in due casi, in cui gli esami sono stati eseguiti senza mezzo di contrasto (MdC) paramagnetico, i focolai flogistici apparivano come lacune di enhancement: singole in 39/123 casi, multiple in 84/123, monolaterali in 60/84 e bilaterali in 24/84. In 40/123 (32,5%) casi positivi sono state rilevate lesioni ascessuali. Durante il follow-up si è dimostrata una regressione completa dei segni RM in 86/103 pazienti; 17/103 casi (16,5%) sono andati incontro ad evoluzione fibrotico-cicatriziale. Nei portatori di rene trapiantato i segni di PNA sono stati evidenziati in 15/35 (42,8%) casi.ConclusioniNella nostra esperienza la RM è risultata uno strumento efficace nella diagnosi e nel follow-up della PNA sia nei soggetti non a rischio, sia nei soggetti a rischio (trapianto renale). Gli elevati costi della metodica sono stati bilanciati dal corretto orientamento del trattamento clinico e dalla tempestiva individuazione delle complicanze.

Low-protein vegetarian diet with alpha-chetoanalogues prior to pre-emptive pancreas-kidney transplantation.

BACKGROUND Pre-emptive pancreas-kidney transplantation is increasingly considered the best therapy for irreversible chronic kidney disease (CKD) in type 1 diabetics. However, the best approach in the wait for transplantation has not yet been defined. AIM To evaluate our experience with a low-protein (0.6 g/kg/day) vegetarian diet supplemented with alpha-chetoanalogues in type 1 diabetic patients in the wait for pancreas-kidney transplantation. METHODS Prospective study. Information on the progression of renal disease, compliance, metabolic control, reasons for choice and for drop-out were recorded prospectively; the data for the subset of patients who underwent the diet while awaiting a pancreas-kidney graft are analysed in this report. RESULTS From November 1998 to April 2004, 9 type 1 diabetic patients, wait-listed or performing tests for wait-listing for pancreas-kidney transplantation, started the diet. All of them were followed by nephrologists and diabetologists, in the context of integrated care. There were 4 males and 5 females; median age 38 years (range 27.9-45.5); median diabetes duration 23.8 years (range 16.6-33.1), 8/9 with widespread organ damage; median creatinine at the start of the diet: 3.2 mg/dl (1.2-7.2); 4 patients followed the diet to transplantation, 2 are presently on the diet, 2 dropped out and started dialysis after a few months, 1 started dialysis (rescue treatment). The nutritional status remained stable, glycemia control improved in 4 patients in the short term and in 2 in the long term, no hyperkalemia, acidosis or other relevant side effect was recorded. Proteinuria decreased in 5 cases, in 3 from the nephrotic range. Albumin levels remained stable; the progression rate was a loss of 0.47 ml/min of creatinine clearance per month (ranging from an increase of 0.06 to a decrease of 2.4 ml/min) during the diet period (estimated by the Cockroft-Gault formula). CONCLUSIONS Low-protein supplemented vegetarian diets may be a useful tool to slow CKD progression whilst awaiting pancreas-kidney transplantation.

Cholesterol crystal embolism syndrome in dialysis patients: an emerging clinical diagnosis?

Background: Cholesterol crystal embolism syndrome (CCE) is an increasing end-stage renal disease cause. Few cases have been described on dialysis, despite the high prevalence of the predisposing factors. Methods: The diagnostic criteria of the present study were: skin lesions, myalgia, fatigue, fever and acute inflammatory serologic signs, in the presence of severe vasculopathy. The precipitating factors were: anticoagulation, endovascular intervention and ulcerated atherosclerotic plaque. Results: Between October 2003 and September 2005, CCE was diagnosed in 6 dialysis patients (of 200–210 on chronic treatment): 5 males, 1 female, median age 59.5 years (47–70) and end-stage renal disease follow-up 11.5 years (3–25). All had severe vasculopathy, 5 cardiopathy, and 4 were failed graft recipients. The treatment included: peritoneal dialysis, daily dialysis, ‘conventional’ hemodialysis (2 cases) and hemodiafiltration. The diagnosis was based on the clinical-laboratory picture in 1 patient. In the 5 others clues were present (dicumarol therapy, angioplasty, femoral artery thrombosis, CCE predialysis and ulcerated aortic plaque). The therapeutic approach consisted of corticosteroids (5 cases), statins (4 cases) and prostaglandin analogues (4 cases). Conclusion: The differential diagnosis of CCE should also be considered in dialysis patients (necrotic lesions, limb pain and vasculitis-like signs).

Renal transplantation in a case of mannosidosis.

Mannosidosis is an inherited autosomal recessive mucopolysaccharidosis. Patients affected accumulate mannose-rich compounds in various tissues and excrete an increased quantity of oligosaccharides with mannose as a component. A case of type II mannosidosis with end-stage renal failure is reported. The patient, after 6 years of regular hemodialysis treatment, received a kidney transplant. At the time this article was written, the graft was functioning well and thesaurismotic renal deposits had not been observed. The clinical course of mannosidosis was silent and the patients quality of life was good. Although the risk of recurrence could not be excluded, it seems that renal transplantation can be safely offered to patients affected with mannosidosis type II, in the rare setting of chronic renal failure.

The role of intravascular coagulation in pregnancy related acute renal failure.

SummaryPregnancy-related acute renal failure (ARF) can include reversible tubular necrosis as well as irreversible cortical necrosis. Though pathogenetic mechanism are not fully understood, disseminated intravascular coagulation (DIC) probably plays a primary role. We report 25 cases of pregnancy-related ARF: 13 were associated with preeclampsia or eclampsia and 12 with obstetric complications. The following parameters were studied: partial thromboplastin, prothrombin and thrombin time, fibrinogen, antithrombin III and FDP levels, platelet count, whole blood clot lysis time and area, fragmented red cells (schistocytes) in the blood smear, hemoglobin, aptoglobin and LDH concentrations. DIC was scored in arbitrary units ranging from 12 to 36 and related to the clinical picture, renal outcome and the treatment employed. Five patients had irreversible renal damage, while 19 recovered fully; one patient died and no renal histology was available. The DIC score did not seem to have a significant relation to the severity of renal damage.

Postpartum acute renal failure in a drug addict

Renal diseases occur in intravenous drug abusers, especially heroin addicts, in the form of interstitial nephritis, nephrotic syndrome or acute renal failure due to rhabdomyolysis. We report a case of acute renal failure not ascribable to rhabdomyolysis nor to the main pathogenetic mechanisms of pregnancy-related acute renal failure in a pregnant heroin addict woman after vaginal delivery following uncomplicated pregnancy. Drug-related immunological abnormalities and microcirculatory distress may be involved.

Atherosclerosis in systemic lupus: The role of antiphospholipid antibodies needs strict diagnostic criteria to be evaluated. Comment on the article by Urowitz et al

In a study published recently in Arthritis Care & Research (1), Urowitz et al report on atherosclerotic vascular events in a multinational inception cohort of systemic lupus erythematosus (SLE) patients. The results of their study show that the significant risk factors did not include antiphospholipid antibodies (aPL). This conclusion is reached because aPL are present in 40% of patients (8 of 20) with vascular events due to atherosclerosis and in 42.9% of patients (15 of 35) with vascular events due to SLE (P 0.84). However, from the data appearing in Table 4, 3 main objections must be considered: 1) there are many missing cases ranging from 5 to 10 in the 2 groups of 22 and 42 patients, respectively, 2) only anticardiolipin antibody (aCL) and lupus anticoagulant (LAC) are cited, and no mention is made of anti– 2-glycoprotein I (anti2GPI) antibodies, and 3) the report of aPL at enrollment alone is cited without mention of a second confirmative result obtained some time later, which is necessary to confirm the presence of persistent, and not just transient, aPL. Furthermore, in Table 3, which compares the 22 patients with atherosclerotic vascular events with the other 615 patients, the only missing data are aPL. Lastly, unlike the study by Urowitz et al, previous studies demonstrated a role for aPL among risk factors for atherosclerotic vascular events in SLE patients (2). The increase of premature cardiovascular disease and subclinical atherosclerosis in SLE patients, which in certain age groups may be 50 times that of an age-matched population, is a hot topic with a growing interest in the last 30 years. This excess risk of cardiovascular disease and atherosclerosis cannot be fully explained by the presence of classic coronary risk factors such as hypertension, diabetes mellitus, premature menopause, sedentary lifestyle, elevated low-density lipoprotein (LDL) cholesterol and triglycerides, insulin resistance, and chronic renal impairment. This increase also involves a range of additional specific “lupus factors,” including chronic inflammation, aPL, and chronic exposure to steroid therapy (3). Particularly, aPL might directly promote atherogenesis through a variety of mechanisms such as alteration of the oxidant–antioxidant balance locally within the vessel wall, cross-reactivity with antibodies to oxidized LDL and to malondialdehyde-modified lipoprotein(a), complement activation, and changes in cytokines activity and role, including TGF -1 activation. It could be argued that thrombosis associated with aPL may occur within blood vessels that are relatively normal histologically, but patients with aPL are more likely to experience a clinical event anyway than those without these markers (3,4), as shown in our experience (5–10). To guarantee the presence of clinically significant aPL, it is mandatory to agree with standard diagnostic criteria, including the spectrum of all required tests (LAC test, moderateto high-titer aCL, or moderateto high-titer 2GPI antibodies) and the differential diagnosis between transient and persistent (6 weeks apart) aPL (4). Also in our experience, the clinical meaning of transient aPL, as compared with persistent aPL, as risk factors for vascular events and global outcomes in SLE patients with renal involvement has been clearly demonstrated. Among 164 patients diagnosed with SLE nephritis (82.7% women, mean age 29 years), the predictive value of aPL antibodies (detected by LAC, aCL, and antiGPI) as risk factors for thrombosis and patient outcome was significantly different in the case of transient or persistent aPL. In fact, compared with aPL-negative patients, aPL-positive patients had a statistically significant increased rate of nonfatal thrombosis (47% versus 5%; P 0.0001) and death (30% versus 12%; P 0.0001); but a further analysis comparing the transient aPL-positive patients with the persistent aPL-positive patients showed that the percentage of patients who developed thrombosis was significantly higher among the 34 persistent aPL-positive patients (70%) than among the 26 transient aPL-positive patients (15%; P 0.0001). In the overall population, thrombosis-free patient survival was 85% at 5 years, 75% at 10 years, 69% at 15 years, and 60% at 20 years. The incidence of the combined end point of thrombosis and death was significantly higher in the aPL-positive group (P 0.0001). In stepwise multivariate analysis, aPL-positivity was a statistically significant predictor of poor survival (hazard ratio [HR] 3.89, 95% confidence interval [95% CI] 1.55–9.81) after adjusting for age, sex, serum creatinine level, and diagnostic period. When the transient and persistent aPL-positive subgroups were compared with the aPL-negative group, there was an even more significant difference in the outcomes; the incidence of the combined end point of thrombosis and