Calciphylaxis: natural history, risk factor analysis, and outcome

[Massive panniculectomy and bilateral subtotal mastectomy in a case of calciphylaxis: A case report and up date]

Calciphylaxis or calcific arteriolopathy is a rare, life-threatening obstructive pathology of the small cutaneous and subcutaneous vessels. It mainly affects patients with chronic renal failure but it also has been described in patients with normal renal function. The principal risks factors apart from renal failure and phosphocalcic metabolism imbalance are: the female sex, obesity, peripheral vascular disease, diabetes and oral anti-coagulation. We present a very rare case of abdominal, mammarian and upper thighs calciphylaxis in a patient with normal renal function. She presented a severe obesity with a recent important loss of weight and had been treated by oral anticoagulants for a long time. She benefited of a multidisciplinary approach with dermatologists, plastic surgeons and anesthesists permitting a recovery in fourteen weeks. Multidisciplinary approach is necessary but the place of the surgery is not well defined. We report a case in which early and wide surgical approach permitted to obtain a favourable evolution of the pathology. Then, we propose a therapeutic strategy after review of the literature.

Calciphylaxis in end-stage renal disease prior to dialytic treatment: a case report and literature review

Introduction

Calciphylaxis is a rare medical condition that is usually diagnosed in patients suffering from end-stage renal disease who are already receiving renal replacement therapy and in those post-transplantation. The pathogenesis still remains to be fully elucidated; hence, the treatment is not uniform. The prognosis is generally poor. The ulcerative stage exhibits a worse prognosis than the nonulcerative one. Calciphylaxis presenting in terminal kidney disease prior to dialytic treatment has only rarely been reported.

Case presentation

A 32-year-old female Caucasian clerk sought medical attention for increasing tiredness and lower limb skin ulcers. Polycystic kidney disease was diagnosed in her late father and two of her siblings. At the first nephrology consultation, obesity, pallor, bilateral flank masses with ballottement, and two ulcers with a dark necrotic center on the distal left leg were noted. In addition, another indurated light bluish lesion of 5 cm just above the right knee with intact skin was observed. All lesions were very tender and warm on touch. Laboratory results yielded hypercalcemia, hyperphosphatemia, anemia, and parathyroid hormone levels that were more than ten times the normal values in the patient, and with a glomerular filtration rate of 4 mL/minute. Skin biopsy confirmed the suspicion of calciphylaxis. The patient was placed on peritoneal dialysis with low Ca concentration baths, cinacalcet, and aluminum hydroxide. The results included correction of hypercalcemia, improvement of phosphate levels, and the product of both Ca and phosphate, but only a transitory decrease in serum parathyroid hormone levels. The ulcerations were completely healed after 2 months of treatment. Cinacalcet was discontinued after 18 months, but multiple large-size, nonulcerative indurated areas appeared 3 months later in the lower limbs after discontinuation of the drug. A parathyroidectomy performed 17 months later revealed a four-gland hyperplastic disease. The patient experienced relief of skin symptoms soon after the procedure and remains in a very satisfactory condition.

Conclusion

Calciphylaxis is a very complex clinical entity. Calciphylaxis presenting prior to dialytic treatment in end-stage renal disease is rare in the absence of a trigger. Cinacalcet and parathyroidectomy should be considered in selected patients.

Bone development and mineral homeostasis in the fetus and neonate: roles of the calciotropic and phosphotropic hormones

Mineral and bone metabolism are regulated differently in utero compared with the adult. The fetal kidneys, intestines, and skeleton are not dominant sources of mineral supply for the fetus. Instead, the placenta meets the fetal need for mineral by actively transporting calcium, phosphorus, and magnesium from the maternal circulation. These minerals are maintained in the fetal circulation at higher concentrations than in the mother and normal adult, and such high levels appear necessary for the developing skeleton to accrete a normal amount of mineral by term. Parathyroid hormone (PTH) and calcitriol circulate at low concentrations in the fetal circulation. Fetal bone development and the regulation of serum minerals are critically dependent on PTH and PTH-related protein, but not vitamin D/calcitriol, fibroblast growth factor-23, calcitonin, or the sex steroids. After birth, the serum calcium falls and phosphorus rises before gradually reaching adult values over the subsequent 24-48 h. The intestines are the main source of mineral for the neonate, while the kidneys reabsorb mineral, and bone turnover contributes mineral to the circulation. This switch in the regulation of mineral homeostasis is triggered by loss of the placenta and a postnatal fall in serum calcium, and is followed in sequence by a rise in PTH and then an increase in calcitriol. Intestinal calcium absorption is initially a passive process facilitated by lactose, but later becomes active and calcitriol-dependent. However, calcitriol's role can be bypassed by increasing the calcium content of the diet, or by parenteral administration of calcium.

Calcific uraemic arteriolopathy: a rare disease with a potentially high impact on chronic kidney disease-mineral and bone disorder

Calciphylaxis [calcific uraemic arteriolopathy (CUA)] is a rare disease at the interface of nephrology, dermatology and cardiology. CUA most often occurs in adult dialysis patients. It is only rarely seen in patients without relevant chronic kidney disease, and only anecdotal reports about childhood calciphylaxis have been published. Clinically, CUA is characterized by a typical cascade, starting with severe pain in initially often inconspicuous skin areas, followed by progressive cutaneous lesions that may develop into deep tissue ulcerations. The typical picture is a mixture of large retiform ulceration with thick eschar surrounded by violaceous, indurated, tender plaques. The histopathological picture reveals arteriolar, often circumferential, calcification and extensive matrix remodelling of the subcutis. These findings explain the macroscopic correlation between skin induration and ulceration. The prognosis in CUA patients is limited due to underlying comorbidities such as uraemic cardiovascular disease and infectious complications. The etiology of CUA is multifactorial, and imbalances between pro- and anti-calcification factors, especially in the setting of end-stage renal disease play an outstanding role. Oral anticoagulant treatment with vitamin K antagonists is a predominant CUA trigger factor. It is speculative as to why children and adolescents only develop calciphylaxis in exceptional cases, although a seldom usage of vitamin K antagonists and the preserved mineral buffering capacity of the growing skeleton may be protective.

Calciphylaxis in a dialysis patient diagnosed by muscle biopsy

Calciphylaxis is a rare condition seen mostly in patients with chronic renal disease and secondary hyperparathyroidism who develop painful skin lesions and myopathy secondary to extensive small vessel calcification, which leads to tissue ischemia. It is typically diagnosed by a biopsy of prominent skin lesions. Here, we report a 49-year-old man with end-stage renal disease on chronic peritoneal dialysis who presented with weakness, myalgias, and necrotic skin lesions. Multiple skin biopsies were nondiagnostic because of severe extensive necrosis, and the diagnosis of systemic calciphylaxis was eventually made by a muscle biopsy. This case demonstrates the significant muscle involvement in calciphylaxis and highlights the importance of maintaining a high clinical suspicion for patients with risk factors for calciphylaxis, even when skin biopsy does not confirm it.

Quantifying a rare disease in administrative data: the example of calciphylaxis

BACKGROUND

Calciphylaxis, a rare disease seen in chronic dialysis patients, is associated with significant morbidity and mortality. As is the case with other rare diseases, the precise epidemiology of calciphylaxis remains unknown. Absence of a unique International Classification of Diseases (ICD) code impedes its identification in large administrative databases such as the United States Renal Data System (USRDS) and hinders patient-oriented research. This study was designed to develop an algorithm to accurately identify cases of calciphylaxis and to examine its incidence and mortality.

DESIGN, PARTICIPANTS, AND MAIN MEASURES

Along with many other diagnoses, calciphylaxis is included in ICD-9 code 275.49, Other Disorders of Calcium Metabolism. Since calciphylaxis is the only disorder listed under this code that requires a skin biopsy for diagnosis, we theorized that simultaneous application of code 275.49 and skin biopsy procedure codes would accurately identify calciphylaxis cases. This novel algorithm was developed using the Partners Research Patient Data Registry (RPDR) (n = 11,451 chronic hemodialysis patients over study period January 2002 to December 2011) using natural language processing and review of medical and pathology records (the gold-standard strategy). We then applied this algorithm to the USRDS to investigate calciphylaxis incidence and mortality.

KEY RESULTS

Comparison of our novel research strategy against the gold standard yielded: sensitivity 89.2%, specificity 99.9%, positive likelihood ratio 3,382.3, negative likelihood ratio 0.11, and area under the curve 0.96. Application of the algorithm to the USRDS identified 649 incident calciphylaxis cases over the study period. Although calciphylaxis is rare, its incidence has been increasing, with a major inflection point during 2006-2007, which corresponded with specific addition of calciphylaxis under code 275.49 in October 2006. Calciphylaxis incidence continued to rise even after limiting the study period to 2007 onwards (from 3.7 to 5.7 per 10,000 chronic hemodialysis patients; r = 0.91, p = 0.02). Mortality rates among calciphylaxis patients were noted to be 2.5-3 times higher than average mortality rates for chronic hemodialysis patients.

CONCLUSIONS

By developing and successfully applying a novel algorithm, we observed a significant increase in calciphylaxis incidence. Because calciphylaxis is associated with extremely high mortality, our study provides valuable information for future patient-oriented calciphylaxis research, and also serves as a template for investigating other rare diseases.

Calciphylaxis and subtotal parathyroidectomy: a double-edged sword

Calciphylaxis, also called calcific uremic arteriolopathy is a dreadful, life-threatening ischemic vasculopathy, primarily involving skin and subcutaneous tissue, mostly on patients with end-stage kidney disease. Calciphylaxis is a well-described, but still a poorly understood disorder of mineral metabolism. Its occurrence is rare, but increasingly reported. We describe a 62-year-old obese lady on hemodialysis for end-stage kidney disease due to type 2 diabetes, who developed two episodes of calciphylactic skin lesions during the 3 years observation. The healing of lesions in the first episode was prompted by a subtotal parathyroidectomy for severe secondary hyperparathyroidism. However, the resumption of oral calcium and vitamin D analog for the parathyroidectomy-related hypocalcemia induced another occurrence of widespread calciphylactic skin lesions in areas of great adiposity. The typical regimen of IV sodium thiosulfate brought a successful outcome to the second episode. Now, growing numbers of successful treatment for calciphylaxis are reported with more specific therapies and a clear understanding of the pathogenetic mechanism is in sight.

Curious case of calciphylaxis leading to acute mitral regurgitation

Calciphylaxis is uncommon and typically seen in patients with end-stage renal disease. It has been defined as a vasculopathic disorder characterised by cutaneous ischaemia and necrosis due to calcification, intimal fibroplasia and thrombosis of pannicular arterioles. We present the case of a 74-year-old woman with chronic kidney disease stage III who developed calciphylaxis leading to mitral valve calcification, chordae tendineae rupture and acute mitral regurgitation. Although an alternative explanation can typically be found for non-uraemic calciphylaxis, her evaluation did not reveal any usual non-uraemic causes including elevated calcium-phosphorus product, hyperparathyroidism, or evidence of connective tissue disease. Her wounds improved with sodium thiosulfate, pamidronate, penicillin and hyperbaric oxygen therapies but she ultimately decompensated with the onset of acute mitral regurgitation attributed to rupture of a previously calcified chordae tendineae. This case highlights an unusual case of calciphylaxis without clear precipitant as well as a novel manifestation of the disease.

Severe anion gap acidosis associated with intravenous sodium thiosulfate administration

INTRODUCTION

Severe anion gap (AG) acidosis associated with intravenous sodium thiosulfate (STS) administration has not been previously described in nondialysis chronic kidney disease (CKD) patients.

CASE REPORT

We present a CKD patient with a baseline creatinine 1.8 mg/dL (eGFR 28 ml/min/1.73 m²) who developed sustained and life-threatening AG acidosis associated with intravenous STS treatment for calciphylaxis.

DISCUSSION

Although marketed as a safe drug, STS can cause life-threatening acidosis as illustrated in this case. STS-induced AG acidosis should be considered in the differential diagnosis of severe acidosis in patients receiving STS. Dosage adjustment and close follow-up of patients' acid-base status after STS initiation is necessary.

Nonuremic calciphylaxis precipitated by teriparatide [rhPTH(1-34)] therapy in the setting of chronic warfarin and glucocorticoid treatment

Calciphylaxis occurs rarely in the absence of end stage renal disease. Predisposing factors for nonuremic calciphylaxis (NUC) include hyperparathyroidism, coagulopathies, connective tissue disease, liver disease, glucocorticoid use, and malignancy. Warfarin can facilitate vascular calcification by reducing vitamin K-dependent carboxylation of matrix-Gla proteins. An 86-year-old Caucasian woman with a history of polymyalgia rheumatica, two spontaneous deep venous thromboses (DVTs) and multiple fractures was treated with calcium, vitamin D, prednisone, and warfarin. The patient's low bone density was treated initially with estrogen, then oral bisphosphonate, which was discontinued due to upper gastrointestinal symptoms. Nasal calcitonin was initiated. After 10 years of calcitonin treatment, she was changed to teriparatide. Two months after initiating teriparatide, she developed lower extremity edema and painful erythematous nodular lesions on her calves bilaterally, that progressed to necrotic ulcers despite antibiotic therapy. Biopsy of the lesions showed calcification in the media of small blood vessels and subcutaneous fat with fat necrosis, consistent with calciphylaxis. Teriparatide was discontinued. Aggressive wound care, antibiotics, and intravenous zoledronic acid were initiated. With cessation of teriparatide therapy and intensive wound care, the patient's lesions resolved over 8 months. We report the first case of NUC precipitated by teriparatide therapy. Our patient had multiple underlying predisposing factors including a connective tissue disorder, glucocorticoid therapy, warfarin use, and possible underlying coagulopathy given her history of multiple DVTs. In such patients, alternative osteoporosis therapies may be preferred.

Falsely increased chloride and missed anion gap elevation during treatment with sodium thiosulfate

BACKGROUND

Sodium thiosulfate (STS) is used to treat calciphylaxis and cyanide poisoning, but can lead to a serious anion-gap acidosis. We suspected that the calculated anion gap in a patient treated with STS for calciphylaxis was decreased to normal by a falsely increased chloride, and we hypothesized that STS directly interfered with chloride measurements.

METHODS

Plasma pools were prepared with 12 concentrations of STS from 0 to 20 mmol/l. Chloride was measured in each sample on 9 analyzers: Architect 16200, StatProfile pHOx Plus, RapidLab 1265®, Vitros 350®, Advia 1800, Roche Modular, iSTAT1, RAPIDpoint 500, and Radiometer ABL735.

RESULTS

Statistically significant, dose-dependent increases in reported chloride concentrations were seen with all analyzers except the RAPIDpoint 500 and Vitros. The increases ranged from 5 to 75 mmol/l at the peak thiosulfate concentrations (33 mmol/l) expected in treated patients. The CLIA-allowable error of 5% was exceeded by 4 analyzers (Architect 16200, iSTAT1, StatProfile pHOx Plus, and Radiometer ABL735). The RAPIDpoint 500 showed a 3-mmol/l decrease in measured chloride over the tested range. The Vitros analyzer showed no interference.

CONCLUSIONS

Interference of STS in chloride measurement in several common analyzers may lead to erroneous anion-gap calculations and confound the diagnosis of STS-induced anion-gap acidosis.

Painful skin ulcers in a hemodialysis patient

Calciphylaxis, also referred to as calcific uremic arteriolopathy, is a relatively rare but well described syndrome that occurs most commonly in patients with late stage CKD. It is characterized by very painful placques or subcutaneous nodules and violaceous, mottled skin lesions that may progress to nonhealing ulcers, tissue necrosis, and gangrene with a 1-year mortality rate >50%. The pathogenesis of calciphylaxis is poorly understood. Risk factors include female sex, obesity, hyperphosphatemia, hypercalcemia, hyperparathyroidism, longer dialysis vintage, hypercoagulable states, and use of calcium-containing phosphate binders and warfarin. Treatment strategies for calciphylaxis are limited by inadequate understanding of its pathophysiology. Therapy is generally focused on correcting disturbances of calcium, phosphorus, and parathyroid hormone metabolism. Additional therapy focuses on decreasing inflammation and on dissolution of tissue calcium deposits with sodium thiosulfate and/or bisphosphonates. Successful treatment generally results in improvement of pain and healing of the lesions within 2-4 weeks, but the disorder generally takes many months to completely resolve.

A case report: radiological findings in an unusual case of calciphylaxis 16 years after renal transplantation

Calciphylaxis is a serious and potentially life-threatening disorder characterized by medial calcification of arterioles leading to subcutaneous ischemia and skin necrosis. It is most commonly seen in patients with end-stage renal disease or shortly after renal transplantation. We report an unusual case of calciphylaxis occurring 16 years after renal transplantation in a 48-year-old female with a failing graft, along with histological and striking radiological findings.

Cutaneous manifestations of ESRD

A broad range of skin diseases occurs in patients with ESRD: from the benign and asymptomatic to the physically disabling and life-threatening. Many of them negatively impact on quality of life. Their early recognition and treatment are essential in reducing morbidity and mortality. The cutaneous manifestations can be divided into two main categories: nonspecific and specific. The nonspecific manifestations are commonly seen and include skin color changes, xerosis, half-and-half nails, and pruritus. The specific disorders include acquired perforating dermatosis, bullous dermatoses, metastatic calcification, and nephrogenic systemic fibrosis. This review article describes these conditions and considers the underlying pathophysiology, clinical presentations, diagnosis, and treatment options.

Multi-modal treatment of calciphylaxis with sodium-thiosulfate, cinacalcet and sevelamer including long-term data

BACKGROUND

Calciphylaxis is a rare, yet life-threatening disease mainly occurring in dialysis patients. Traditional options of treatment remain unsatisfactory.

METHODS

Here we present a novel, combined approach, treating calciphylaxis with IV sodium thiosulfate, cinacalcet and sevelamer. In a case series five hemodialysis patients, have been successfully treated with this regimen. Treatment and survival data were analyzed using descriptive statistics.

RESULTS

In all patients, a rapid decrease in pain, improvement of general condition and wound healing within six months occurred. Side effects were low. Drug dosages: IV sodium thiosulfate initial dose 119.4 +/- 84.9 g/m(2)/week, maintenance dose 40.6 +/- 9 g/m(2)/week; cinacalcet: maintenance dose 36 +/- 32.9 mg/d and sevelamer maintenance dose 3320 +/-1671 mg/d. One and two year survivals were 100 % and 80 %, respectively. We also report on long-term application of IV sodium thiosulfate of up to 52 months. Patient survival after diagnosis was 52, 84, 21, 36 and 30 months, respectively. Survival since initiation of hemodialysis was 76, 136, 89, 36 and 35 months, respectively.

CONCLUSION

This novel combined approach, a multi-modal treatment of calciphylaxis with persistent hyperparathyroidism, using IV sodium thiosulfate, cinacalcet and sevelamer seems to improve the outcome of this devastating disease.

Calcific Uremic Arteriolopathy

Calcific uremic arteriolopathy is a little understood diagnosis of increasing prevalence seen predominantly in patients with chronic kidney disease, particularly those who are approaching end-stage renal disease, who are undergoing renal dialysis, and who have secondary hyperparathyroidism. Calcific uremic arteriolopathy affects women more frequently than men, at a ratio of 3:1, and the median age at diagnosis is 48 years. A clear understanding of the pathogenesis and definitive plans of care are lacking. Nurses should be familiar with the clinical picture of calcific uremic arteriolopathy. Early recognition is important to develop optimal treatment plans and to limit progression of this rare but often fatal disease. Nurses have a pivotal role in maintaining the patient’s comfort and dignity, while setting realistic goals of care. Calcific uremic arteriolopathy remains a rare and complex clinical condition that requires a multidisciplinary health care team approach to provide the optimal level of care. Nurses have an essential role in the care of patients with the diagnosis of calcific uremic arteriolopathy.

Penile calciphylaxis in end stage renal disease

Calciphylaxis, better described as "Calcific uremic arteriolopathy" (CUA), involves about 1-4% of hemodialysis patients all around the world with high mortality rates. We describe a rare clinical case of CUA in peritoneal dialysis patient associated with urological disease. Penile calciphylaxis represents rare clinical complication, and an early diagnosis and multidisciplinary approach are requested. Pathogenesis is still unclear, and therapeutic approaches need more long-term clinical trials to test their efficacy and safety.

Update on cutaneous calciphylaxis

Calciphylaxis is a devastating disorder with a mortality rate of 80% due to sepsis and organ failure. Hallmarks of this rare disease are arteriolar media calcification, thrombotic cutaneous ischemia, and necrotic ulcerations. Different mechanisms of vascular calcification can lead to calciphylaxis. Early diagnosis by deep cutaneous ulcer biopsy is most important for prognosis. Here, dermatologists play a significant role although treatment usually needs an interdisciplinary approach. Surgical procedures had been the cornerstone of treatment in the past including parathyroidectomy, but recently new medical treatments emerged aiming to normalize disturbances of minerals to reduce the serum concentration of sodium phosphate and to prevent precipitation and calcification. Multimodal therapy is warranted but only aggressive surgical debridement of cutaneous ulcers has shown significant outcome improvement.

Revascularization surgery for penile calciphylaxis

Calciphylaxis, a systemic disorder seen in 1%-4% of patients with end-stage renal disease, is a cause of penile ischemic gangrene. We present a case of successful revascularization surgery for penile calciphylaxis. An arterial bypass to the deep dorsal penile vein relieved the rest pain and stopped expansion of the gangrenous lesion.

Calciphylaxis and sodium thiosulphate: a glimmer of hope in desperate situation

BACKGROUND

Calciphylaxis is an uncommon and often under diagnosed condition affecting patients undergoing chronic dialysis. Its pathogenesis is poorly understood. The abnormalities of calcium, phosphate and parathyroid hormone homeostasis leading to vascular calcification and ischaemic skin necrosis are thought to be the central problem. Meticulous wound care and aggressive metabolic control remain the cornerstone of the treatment; however, the overall benefit of these treatment options remains low and mortality and morbidity remain very high. Sodium thiosulphate is an inorganic salt, which is used for treating acute cyanide poisoning, recurrent calcium urolithiasis and nephrocalcinosis. Recently, it has also been reported to be useful in treating severe cases of calciphylaxis with promising results.

METHODS

A resistant case of calciphylaxis in a patient on long-term haemodialysis was treated with sodium thiosulphate (50 ml solution with 50% sodium thiosulphate) three times a week during the end of each dialysis session.

RESULTS

The skin lesions started to heal after two weeks and completely resolved after five months of treatment.

CONCLUSIONS

Sodium thiosulphate can be a safe and effective treatment option for resistant and severe cases of calciphylaxis.

Warfarin accelerates ectopic mineralization in Abcc6(-/-) mice: clinical relevance to pseudoxanthoma elasticum

Pseudoxanthoma elasticum (PXE) is a multisystem ectopic mineralization disorder caused by mutations in the ABCC6 gene. Warfarin, a commonly used anticoagulant, is associated with increased mineralization of the arterial blood vessels and cardiac valves. We hypothesized that warfarin may accelerate ectopic tissue mineralization in PXE, with clinical consequences. To test this hypothesis, we developed a model in which Abcc6(-/-) mice, which recapitulate features of PXE, were fed a diet supplemented with warfarin and vitamin K1. Warfarin action was confirmed by significantly increased serum levels of oxidized vitamin K. For mice placed on a warfarin-containing diet, quantitative chemical and morphometric analyses revealed massive accumulation of mineral deposits in a number of tissues. Mice fed a warfarin-containing diet were also shown to have abundant uncarboxylated form of matrix Gla protein, which allowed progressive tissue mineralization to ensue. To explore the clinical relevance of these findings, 1747 patients with PXE from the approximately 4000 patients in the PXE International database were surveyed about the use of warfarin. Of the 539 respondents, 2.6% reported past or present use of warfarin. Based on the prevalence of PXE (approximately 1:50,000), thousands of patients with PXE worldwide may be at risk for worsening of PXE as a result of warfarin therapy.

Statin use and calcific uremic arteriolopathy: a matched case-control study

BACKGROUND

Calcific uremic arteriolopathy (CUA), also known as calciphylaxis, is characterized by vascular calcification, thrombosis and intense inflammation. Prior research has shown that statins have anticalcification, antithrombotic and antiinflammatory properties; however, the association between statin use and CUA has not been investigated.

METHODS

This matched case-control study included 62 adult maintenance hemodialysis (HD) patients with biopsy-confirmed CUA diagnosed between the years 2002 and 2011 (cases). All cases were hospitalized at the time of diagnosis. Controls (n = 124) were hospitalized maintenance HD patients without CUA (matched to cases by gender and timing of hospitalization). Univariate and multivariable logistic regression models were applied to compute odds ratio (OR) and 95% confidence intervals (CI) for CUA in statin users, and also to examine previously described associations.

RESULTS

The mean age of cases was 58 years. Most were females (68%), and of white race (64%). Statin use was more common in controls than in cases (39 vs. 19%, p < 0.01). Statin use was associated with lower odds of CUA in unadjusted (OR 0.38, 95% CI 0.18-0.79) and adjusted (OR 0.20, 95% CI 0.05-0.88) analyses. Hypercalcemia (OR 2.25, 95% CI 1.14-4.43), hypoalbuminemia (OR 5.73, 95% CI 2.79-11.77), calcitriol use (OR 5.69, 95% CI 1.02-31.77) and warfarin use (OR 4.30, 95% CI 1.57-11.74) were positively associated with CUA in adjusted analyses whereas paricalcitol and doxercalciferol were not (OR 1.33, 95% CI 0.54-3.27).

CONCLUSION

Statin use may be negatively associated with odds of CUA. Further large prospective studies with attention to potential confounders are needed to confirm these findings.

Sodium thiosulfate therapy for calcific uremic arteriolopathy

BACKGROUND AND OBJECTIVE

Calcific uremic arteriolopathy (CUA) is an often fatal condition with no effective treatment. Multiple case reports and case series have described intravenous sodium thiosulfate (STS) administration in CUA, but no studies have systematically evaluated this treatment.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

This study included 172 patients undergoing maintenance hemodialysis who had CUA and were treated with STS between August 2006 and June 2009 at Fresenius Medical Care North America. Of these, 85% completed STS therapy. Clinical, laboratory, and mortality data were abstracted from clinical information systems. Responses to survey questionnaires sent to treating physicians regarding patient-level outcomes were available for 53 patients. Effect on CUA lesions and mortality were summarized as CUA outcomes. Relevant laboratory measures, weight (using pairwise comparisons of values before, during, and after STS), and adverse events were summarized as safety parameters.

RESULTS

Mean age of the cohort was 55 years, and 74% of patients were women. Median STS dose was 25 g, and median number of doses was 38. Among surveyed patients, CUA completely resolved in 26.4%, markedly improved in 18.9%, improved in 28.3%, and did not improve in 5.7%; in the remaining patients (20.8%), the response was unknown. One-year mortality in patients treated with STS was 35%. Adverse events, laboratory abnormalities, and weight-related changes were mild. Significant reductions in serum phosphorous (P=0.02) and parathyroid hormone (P=0.01) were noted during STS treatment in patients who completed the therapy.

CONCLUSIONS

Although conclusive evidence regarding its efficacy is lacking, a majority of patients who received STS demonstrated clinical improvement in this study.

Restricting dietary magnesium accelerates ectopic connective tissue mineralization in a mouse model of pseudoxanthoma elasticum (Abcc6(-/-) )

Ectopic mineralization, linked to a number of diseases, is a major cause of morbidity and mortality in humans. Pseudoxanthoma elasticum (PXE) is a heritable multisystem disorder characterized by calcium phosphate deposition in various tissues. The mineral content of diet has been suggested to modify the disease severity in PXE. The aim of this study is to explore the role of diet with reduced magnesium in modifying tissue mineralization in a mouse model of PXE. Abcc6(-/-) mice were placed on either standard rodent diet (control) or an experimental diet low in magnesium at weaning (4 weeks) and examined for mineralization in the skin and internal organs at the ages of 1.5, 2 or 6 months by computerized morphometric analysis of histopathological sections and by chemical assay of calcium and phosphate. Abcc6(-/-) mice on experimental diet demonstrated an accelerated, early-onset mineralization of connective tissues, as compared to control mice. Wild-type or heterozygous mice on experimental diet did not show evidence of mineralization up to 6 months of age. All mice on experimental diet showed decreased urinary calcium, increased urinary phosphate and elevated parathyroid serum levels. However, no difference in bone density at 6 months of age was noted. Our findings indicate that the mineral content, particularly magnesium, can modify the extent and the onset of mineralization in Abcc6(-/-) mice and suggest that dietary magnesium levels may contribute to the phenotypic variability of PXE. The control of mineralization by dietary magnesium may have broader implications in general population in the context of vascular mineralization.

An unusual site for calciphylaxis: a case report

BACKGROUND

Calciphylaxis is a rare condition characterized by calcification of the tunica media of small arteries with or without endovascular fibrosis, extravascular calcification and vascular thrombosis, leading to tissue ischemia and hence necrosis of tissues supplied by respective vessel.

CASE REPORT

An 83-year-old lady presented with a 2-week history of rapidly progressing painful necrotic vulval lesion. This patient was being treated medically with bisphosphonates for mild hypercalcaemia secondary to a parathyroid adenoma. The diagnosis of calciphylaxis was made by biopsy of lesion, revealing extensive necrotic areas and multiple abscesses with numerous thrombosed and calcified blood vessels.

CONCLUSIONS

This case shows an unusual presentation of calciphylaxis, in a patient with primary hyperparathyroidism, in the absence of end stage renal failure. The pathogenesis of the condition is still relatively unknown. Particularly of note in this case is the presentation of the lesion 9 months after the start of treatment with bisphosphonate after the relative decrease of serum parathyroid levels and serum calcium levels. This leads to the question of initiation of the pathology - did the bisphosphonate treatment have an input in initiation of the lesion? The case under review adds a new differential diagnosis to necrotic vulval lesions, other than malignancy.

Diagnosis of common dermopathies in dialysis patients: a review and update

Cutaneous abnormalities in patients with end-stage renal disease (ESRD) receiving hemodialysis or peritoneal dialysis may demonstrate signs of their underlying condition or reveal associated disease entities. While a thorough examination of the scalp, skin, mucosa, and nails is integral to establishing a diagnosis, certain conditions will resolve only with dialysis or improvement of their renal disease and others may not require or respond to treatment. Half and half nails, pruritus, xerosis, and cutaneous hyperpigmentation are common manifestations in ESRD. With hemodialysis, uremic frost is no longer prevalent in ESRD patients and ecchymoses have decreased in incidence. Acquired perforating dermatoses are seen in over one-tenth of hemodialysis patients. Metastatic calcinosis cutis and calciphylaxis are both rarely reported, although the latter is seen almost exclusively in the setting of hemodialysis. Diagnosis of nephrogenic systemic fibrosis has historically been challenging; as such, new diagnostic criteria have been proposed. Blood porphyrin profiles are needed to differentiate between porphyria cutanea tarda and pseudoporphyria. We will review and provide an update on the aforementioned common cutaneous manifestations of ESRD in patients receiving dialysis.

Use of sodium thiosulphate in a multi-interventional setting for the treatment of calciphylaxis in dialysis patients

BACKGROUND

Calciphylaxis is a life-threatening complication in patients with end-stage renal disease (ESRD). No established therapy exists so far. The aim of the present study was to determine the therapeutic response to a multi-interventional treatment regimen with consistent use of sodium thiosulphate (STS) in an Austrian cohort of calciphylaxis patients.

METHODS

We retrospectively collected demographic, clinical and laboratory data on 27 calciphylaxis patients treated with STS at seven Austrian dialysis centres between June 2004 and November 2010.

RESULTS

Twenty-seven dialysis patients (68 ± 12 years) were treated with STS for a median (25th, 75th percentile) of 96 (54, 133) days. Seven patients (26%) suffered from proximal-type, and 20 patients (74%) from distal-type calciphylaxis. Fourteen patients (52%) showed a complete remission, five patients (19%) a partial remission and eight patients (30%) progression that resulted in amputation in four patients. During a median follow-up of 101 (79, 273) days, 14 patients died (52%). Non-survivors were older (P = 0.04), showed higher CRP values (P = 0.04), presented more frequently with proximal-type calciphylaxis (P = 0.03), had a higher disease severity score at diagnosis (P = 0.01), were treated more often with antibiotics (P = 0.01) and cinacalcet (P = 0.03) and had a lower remission rate during treatment (P = 0.004) than did survivors. The use of antibiotics and cinacalcet, disease severity at diagnosis and remission rates were found to be significant survival predictors in logistic regression analysis.

CONCLUSIONS

Calciphylaxis remains a serious complication with high mortality. Early and consistent therapy including STS may help to improve the disease outcome.

Calciphylaxis: a report of six cases and review of literature

Calciphylaxis is usually a fatal condition that develops in a few chronic renal failure patients, and it is characterized by calcifications in subcutaneous arteries, infarcts in skin, and the neighboring subcutis. Calciphylaxis, once considered as a rare condition, has been reported to have an annual incidence of 1% and a prevalence of 4% in dialysis patients. We describe our clinical experience in six end-stage renal disease patients on dialysis that presented with calciphylaxis and died due to sepsis, and review the pathogenesis, epidemiology, clinical and histopathologic features, and treatment of calciphylaxis. Physicians should initially consider the possibility of calciphylaxis in case of development of skin lesions in chronic renal failure patients with impaired calcium, phosphorus, and parathyroid hormone levels. The most important cause of mortality in this condition is infection. Therefore, differential diagnosis of these lesions from systemic vasculitis in their early stages and withdrawal of immunosuppressive therapy that increases the tendency to infections are essential.

Compression of the dorsalis pedis artery: a novel cause of blue toe syndrome

Blue toe syndrome (BTS) is an important vascular condition characterized by painful blue discoloration of one or more digits. It is frequently due to emboli and is important because of the risk of progressive ischemia and tissue loss. A 53-year-old male presented with recurrent episodes of painful blue discoloration and blistering of the skin of the right hallux. On examination, the patient was found to have a cool, blue-purple great toe; all peripheral pulses were present. The patient was investigated for coagulopathy and potential sources of emboli, but the only abnormality was significant stenosis of the dorsalis pedis artery due to extrinsic compression by the extensor hallucis brevis tendon. In the absence of any other embolic source or abnormality, we believe that this case presents a novel and potentially remediable cause of BTS and indicates the need for a careful search for an underlying lesion when common causes of BTS have been excluded.

Case Report on Calciphylaxis: An Early Diagnosis and Treatment May Improve Outcome

This is a case report of a patient who presented to the wound care center with LE ulcerations that were subsequently diagnosed with calciphylaxis. She was an insulin dependent diabetic with renal disease, but unaware of her critical kidney status. She was treated with local wound care, a partial parathyroidectomy, and started on dialysis. She is currently healed with no recurrence of ulcerations. Her ulcerations were controlled with conservative wound care and no surgical debridement.

Calciphylaxis following coronary artery bypass surgery: an underappreciated cause of wound complications?

Wound complications following cardiac surgery are typically infectious and associated with a high morbidity and mortality. Calciphylaxis, vascular calcification of small and medium sized vessels, often associated with end-stage renal disease, can result in extensive tissue necrosis. We hypothesize that calciphylaxis is an under-recognized and under-reported precipitating wound and breast complication following coronary artery bypass surgery and thereby necessitates further study.

Net-like pattern of calcification on plain soft-tissue radiographs in patients with calciphylaxis

BACKGROUND

Calciphylaxis is a rare, life-threatening syndrome marked by vascular calcification and cutaneous necrosis. The role of radiographic imaging in assisting in diagnosis has not been established.

OBJECTIVE

To investigate the potential role of plain radiographic imaging in the diagnosis of calciphylaxis.

METHODS

We searched for cases of patients at our tertiary referral center with a diagnosis of calciphylaxis between Jan 1, 1996, and Dec 31, 2010. Two control patients receiving dialysis but without calciphylaxis were age- and sex-matched to each study patient. Plain radiographs were obtained from the date closest to diagnosis in patients with calciphylaxis and from matched controls at approximately the same dates. Two radiologists, masked as to cases and controls, read each image together. Size of calcified vessels, pattern and extent of calcifications, presence of net-like or other calcifications, and bone density/mineralization were recorded and analyzed.

RESULTS

Twenty-nine patients with calciphylaxis (mean age, 57 years; 21 [72%] women) were identified. Mean age at diagnosis was 57 years (range, 36-75 years). Compared with those of controls, plain radiographs of patients with calciphylaxis had more vascular calcifications, more small-vessel calcifications, and a netlike pattern of calcifications. A netlike pattern of calcifications had considerable strength of association with calciphylaxis (odds ratio, 9.4) and a specificity of nearly 90%. These findings were preserved even if only one image was used per patient.

LIMITATIONS

This was a retrospective study.

CONCLUSION

A netlike pattern of calcifications on plain radiographs was more common in patients with calciphylaxis and may aid in diagnosis.

Calciphylaxis with normal renal function: treated with intravenous sodium thiosulfate

Calciphylaxis is a rare and potentially life-threatening condition. It is thought to result from arterial calcification causing complete vascular occlusion and subsequent cutaneous infarction. Most often, it is a complication of end-stage renal failure or hyperparathyroidism; without either of these associated conditions, it is extremely rare. We report a case of calciphylaxis in a 58-year-old white British man, who had received long-term oral prednisolone for asthma control, with prophylactic calcium supplementation. There was no history of renal failure, and the patient's parathyroid function was normal. He was found to be heterozygous for the Factor V Leiden mutation. The acute presentation was seemingly precipitated by an episode of trauma and subsequent compression bandaging. The patient responded promptly to intravenous sodium thiosulfate. To our knowledge, this is the first case with no history of renal failure and normal parathyroid function, precipitated by compression bandaging and with an associated Factor V Leiden mutation.

Successful treatment of calcific uremic arteriolopathy with sodium thiosulfate in a renal transplant recipient

Abstract Calcific uremic arteriolopathy (CUA) is a rare but life-threatening disorder of arteriolar calcification. It frequently leads to severe ischemia, intense pain, and tissue necrosis with non-healing skin ulcerations. CUA usually occurs in patients with chronic kidney disease (CKD), especially those on dialysis, and its occurrence is rare in kidney transplant recipients. The treatment of this disorder is not clearly defined, and no randomized prospective trials are available. Treatment has focused on optimizing dialysis treatment, control of bone mineral parameters, wound care, experimental anticalcification therapies-using bisphosphonates, cinacalcet, parathyroidectomy, and hyperbaric oxygen. Such treatments are based on the pathophysiological considerations and evidences from case reports or series. Recently, several cases have reported about the emerging benefits of intravenous sodium thiosulfate (STS) in the treatment of CUA. STS has resulted in rapid pain relief, wound healing, and prevention of death. We report a case of CUA in a 63-year-old Caucasian man with a functioning renal allograft. In this patient, intravenous STS was administered for 8 months, which was the principal therapy, which resulted in complete resolution of the CUA and skin healing.