Calciphylaxis in CKD and beyond

Clinical characteristics and prognosis of dialysis patients with metastatic calcification diagnosed by 99mTc-MDP bone scintigraphy

To analyze the clinical characteristics of patients with metastatic calcification undergoing maintenance dialysis. Patients diagnosed with metastatic calcification via 99mTc-MDP bone scintigraphy between June 2019 and March 2023 at our hospital were included in this study. All patients were followed from the time of diagnosis until death, loss to follow-up, or the study endpoint (July 2023). The primary endpoint was all-cause mortality. The cohort comprised 7 males and 3 females, with a mean age of (48.7 ± 11.1) years. The most common sites of metastatic calcification included the lungs, joints, and skin, while rarer sites involved the stomach, myocardium, and mandibular angle. Nine patients received treatment with sodium thiosulfate, with a mean duration of STS administration of 23.5 days (range: 13.25 to 56.5 days). The mean follow-up duration was 14 months (range: 10 to 20 months). One patient died, one was lost to follow-up, while 8 out of 10 patients survived, and 6 out of 10 patients were followed for more than one year. 99mTc-MDP bone scintigraphy demonstrates high sensitivity and specificity for detecting metastatic calcification. The most frequently affected sites are the lungs, joints, and skin, with less common sites being the stomach, myocardium, and mandibular angle. Eight patients (8/10) survived, and 6 patients (6/10) remained alive with over one year of follow-up.

A Rare Case of Calciphylaxis: A Case Report

Introduction

Calciphylaxis is a rare and severe disorder characterized by obstructive small vessel disease in the subcutaneous adipose tissue and skin, leading to necrotic skin lesions. The condition poses a significant risk of mortality due to infectious and ischemic complications.

Case Presentation

We present the case of a 60-year-old woman, with a history of renal lithiasis, hypertension, and end-stage renal disease on hemodialysis complicated by hyperparathyroidism and aortic valve replacement. She developed extensive necrotic lesions on both lower limbs and upper extremities, prompting a diagnosis of calciphylaxis. Radiographic and biopsy findings supported the diagnosis, revealing characteristic calcifications. Treatment involved antibiotics, oral thiosulfate, daily hemodialysis, hyperbaric oxygen therapy, and discontinuation of calcium and alfacalcidol, with alendronate initiation. Unfortunately, despite these interventions, the patient experienced a rapid clinical decline, developing septic shock necessitating bilateral leg amputations. Regrettably, she succumbed to the disease 10 days later.

Conclusion

This case underscores the challenging prognosis of calciphylaxis and the need for effective therapeutic options, including surgical intervention and access to injectable thiosulfate.

The Accelerated Onset of Calciphylaxis in a 72-Year-Old Female Hemodialysis Patient

Calciphylaxis is a unique medical condition characterized by calcification of the medial layer of arterioles and soft tissues in a patient's skin at the level of the dermis and subcutaneous adipose tissue. The rate of progression of calciphylaxis is rapid, starting with a reduction of blood flow that leads to ischemic changes in the skin that can manifest as painful cutaneous erythematous nodules or plaques and later as skin ulceration. The majority of patients affected by calciphylaxis have predisposing comorbidities such as end-stage renal disease with a long history of hemodialysis and electrolyte abnormalities in calcium, phosphate, and parathyroid hormone levels. This report presents the case of a 72-year-old female patient on hemodialysis who developed calciphylaxis. The methods for early prognosis (the methods of early diagnosis), including clinical presentation, risk factors, imaging techniques, and laboratory investigations, are discussed. The presented case is particularly noteworthy given the onset of calciphylaxis within a mere three months of initiating hemodialysis, a timeline significantly shorter than the typically observed period in most patients. (The case detailed in this report outlines the rapid onset of calciphylaxis in a patient who was receiving hemodialysis for only three months.) This patient with early-onset calciphylaxis highlights the unpredictable nature of calciphylaxis and the need for increased clinical vigilance even in the initial stages of hemodialysis.

The application of MDT model for calciphylaxis management in patients with end-stage renal disease

This study focuses on the application of nurse-led multidisciplinary collaborative therapy (MDT) management model for calciphylaxis prevention of patients with terminal renal disease. Through the establishment of a multidisciplinary management team spanning nephrology department, blood purification center, dermatology department, burn and plastic surgery department, infection department, stem cell platform, nutrition department, pain department, cardiology department, hydrotherapy group, dermatology group, and outpatient treatment room, the distribution of duties among team members were clarified to bring out the best advantages of a multidisciplinary teamwork during treatment and nursing. For patients with calciphylaxis symptoms in terminal renal disease, a case-by-case management model was carried out with the focus on personalised problem. We emphasised on personalised wound care, precise medication care, active pain management, psychological intervention and palliative care, the amelioration of calcium and phosphorus metabolism disorder, nutritional supplementation, and the therapeutic intervention based on human amniotic mesenchymal stem cell regeneration. The MDT model effectively compensates for traditional nursing mode and could serve as a novel clinical management modality for calciphylaxis prevention in patients with terminal renal disease.

Multimodality approach to treat calciphylaxis in end-stage kidney disease patients

A multimodality approach has been proposed as an effective treatment for calciphylaxis in patients with end-stage kidney disease. In this retrospective study, we report the cases of 12 end-stage kidney disease patients from l'Hôtel-Dieu de Québec hospital (Canada) who were diagnosed with calciphylaxis between 2004 and 2012 and treated with a multimodality clinical approach including sodium thiosulfate (STS). Statistical analyses were performed to evaluate the impacts of patients characteristics, the different interventions as well as therapy regimen on the therapeutic response. The majority of patients (n = 9) were hemodialyzed. The patients-associated comorbidities were consistent with previously reported risk factors for calciphylaxis: Diabetes (n = 11), calcium-based phosphate binders use (n = 10), warfarin use (n = 9), obesity (n = 7), female gender (n = 8) and intravenous iron use (n = 8). STS was given for a median duration of 81 days. 75% of the patients had a response (total or partial) including a complete response in 42% of patients. One-year mortality rate was low (25%). STS was used during a mean duration of 83.33 ± 41.52 days and with a total cumulating dose of 1129.00 ± 490.58 g. The recorded mean time before a complete response was 102.20 days (51-143). Pain improvement occurred after a mean time of 8.67 ± 10.06 days. None of the studied factors was statistically associated with a complete or a partial response to the multimodality approach. Although our data have a limited statistical power, they support treating calciphylaxis with a multimodality approach including STS as its effects are independent from important clinical variables.

Clinical mimickers of calciphylaxis: A retrospective study

BACKGROUND

Calciphylaxis is an ischemic vasculopathy with high morbidity and mortality. Early and accurate diagnosis is critical to management of calciphylaxis. Clinical mimickers may contribute to delayed or misdiagnosis.

OBJECTIVE

To assess the rate and risk factors for misdiagnosis and to identify clinical mimickers of calciphylaxis.

METHODS

A retrospective medical record review was conducted of patients with calciphylaxis at a large urban tertiary care hospital between 2006 and 2018.

RESULTS

Of 119 patients diagnosed with calciphylaxis, 73.1% were initially misdiagnosed. Of patients not initially misdiagnosed, median time to diagnosis from initial presentation was 4.5 days (interquartile range, 1.0-23.3), compared to 33 days (interquartile range, 13.0-68.8) in patients who were initially misdiagnosed (P = .0002). The most common misdiagnoses were cellulitis (31.0%), unspecified skin infection (8.0%), and peripheral vascular disease (6.9%). Patients who were misdiagnosed frequently received at least 1 course of antibiotics. Patients with end-stage renal disease were less likely to be misdiagnosed than those without this disease (P = .001).

LIMITATIONS

Single-center, retrospective study.

CONCLUSIONS

Understanding the risk factors for misdiagnosis of calciphylaxis is an opportunity for further education concerning this rare disease.

Cardiovascular and Bleeding Outcomes with Anticoagulants across Kidney Disease Stages: Analysis of a National US Cohort

BACKGROUND

While direct oral anticoagulants (DOACs) are considered safe among patients without chronic kidney disease (CKD), the evidence is conflicting as to whether they are also safe in the CKD and end-stage kidney disease (ESKD) population. In this observational cohort study, we examined whether DOACs are a safe alternative to warfarin across CKD stages for a variety of anticoagulation indications.

METHODS

Individuals on DOACs or warfarin were identified from OptumLabs® Data Warehouse (OLDW), a longitudinal dataset with de-identified administrative claims, from 2010 to 2017. Cox models with sensitivity analyses were used to assess the risk of cardiovascular disease and bleeding outcomes stratified by CKD stage.

RESULTS

Among 351,407 patients on anticoagulation, 45% were on DOACs. CKD stages 3-5 and ESKD patients comprised approximately 12% of the cohort. The most common indications for anticoagulation were atrial fibrillation (AF, 44%) and venous thromboembolism (VTE, 23%). DOACs were associated with a 22% decrease in the risk of cardiovascular outcomes (HR 0.78, 95% CI: 0.77-0.80, p < 0.001) and a 10% decrease in the risk of bleeding outcomes (HR 0.90, 95% CI: 0.88-0.92, p < 0.001) compared to warfarin after adjustment. On stratified analyses, DOACs maintained a superior safety profile across CKD stages. Patients with AF on DOACs had a consistently lower risk of cardiovascular and bleeding events than warfarin-treated patients, while among other indications (VTE, peripheral vascular disease, and arterial embolism), the risk of cardiovascular and bleeding events was the same among DOAC and warfarin users.

CONCLUSION

DOACs may be a safer alternative to warfarin even among CKD and ESKD patients.

Assessment of outcomes of calciphylaxis

BACKGROUND

Calciphylaxis is a rare thrombotic vasculopathy characterized by high morbidity and mortality. There is a paucity of studies examining longitudinal outcomes.

OBJECTIVE

To assess mortality, days spent in the hospital, and amputations in patients with calciphylaxis.

METHODS

A retrospective medical record review was conducted in 145 patients diagnosed with calciphylaxis at an urban tertiary care hospital from January 2006 to December 2018.

RESULTS

Six-month mortality was 37.2%, and 1-year mortality was 44.1%. Patients with nephrogenic calciphylaxis had worse survival than those with nonnephrogenic calciphylaxis (P = .007). This difference in survival disappeared when limiting mortality to deaths due to calciphylaxis. Age (P = .003) and end-stage renal disease (P = .01) were risk factors associated with 1-year mortality. Diabetes mellitus was associated with greater total hospitalization days (coefficient, 1.1; 95% confidence interval, 1.01-1.4); bedside debridement was associated with fewer hospitalization days (coefficient, 0.8; 95% confidence interval, 0.7-0.9). Amputations were not associated with any of the examined risk factors. The use of warfarin followed by a transition to nonwarfarin anticoagulation was associated with decreased hazard of death (P = .01).

LIMITATIONS

Retrospective nature.

CONCLUSIONS

Calciphylaxis remains a complex, heterogeneous disease. Mortality is lower in patients with nonnephrogenic disease. These findings may be incorporated during discussions regarding the goals of care to facilitate informed shared decision making.

Penile calciphylaxis: A retrospective case-control study

BACKGROUND

Calciphylaxis is a rare disorder characterized by skin necrosis caused by calcium deposition within vessels, thrombosis, and subsequent tissue ischemia. Penile involvement may rarely occur.

OBJECTIVE

To identify risk factors, diagnosis, management, and mortality of patients with penile calciphylaxis.

METHODS

A retrospective medical record review was conducted of 16 patients with penile calciphylaxis treated at 2 large urban tertiary care centers between January 2001 and December 2019. A control group of 44 male patients with nonpenile calciphylaxis at the same institution was included.

RESULTS

The median survival of patients with penile calciphylaxis was 3.8 months (interquartile range, 27.0 months). Mortality was 50% at 3 months and 62.5% at 6 months for penile calciphylaxis, and 13.6% at 3 months and 29.5% at 6 months for controls (P = .008). Patients with penile calciphylaxis were less likely to be obese (P = .04) but more likely to have hyperparathyroidism (P = .0003) and end-stage renal disease (P = .049).

LIMITATIONS

Retrospective study design and small sample size.

CONCLUSIONS

This study further defines the disease course of penile calciphylaxis, which has high mortality. Imaging may be used to aid diagnosis. Risk factors include end-stage renal disease, hyperparathyroidism, and normal body mass index.

[Hyperthyroidism-induced calciphylaxis: A case report]

BACKGROUND

Calciphylaxis or calcific uremic arteriolopathy (CUA) is a cutaneous disease with ulcerations secondary to calcification of cutaneous and subcutaneous small arteries and arterioles. It is a rare but severe disease with significant morbidity and mortality affecting 1 to 4% of dialysis patients. The circumstances of occurrence are multiple.

CASE

We report the case of a severe bilateral lower limb calciphylaxis in a 69-year-old, obese, hemodialysis patient with a recent diagnosis of Graves' disease complicated with hypercalcemia and cardiac arrhythmia requiring the use of vitamin K antagonist. Complex and multidisciplinary therapeutic management (daily hemodialysis, sodium thiosulfate therapy, treatment of hypercalcemia by denosumab, hyperbaric oxygen therapy, meshed skin autograft) allowed complete healing of the lesions.

CONCLUSION

This is the first description of AUC secondary to hyperthyroidism in a dialysis patient. Multidisciplinary care is essential to achieve clinical improvement in those critical situations.

Chronic Kidney Disease and Calciphylaxis: A Literature Review

Calcific uremic arteriolopathy (CUA), also known as calciphylaxis, is a rare complication of chronic kidney disease (CKD). Its incidence is increasing due to a better understanding and diagnosis by physicians. Calciphylaxis is a fatal complication of many metabolic disorders. If not managed properly, it can lead to death within a year. This review is an effort to highlight the importance of research on prompt diagnosis and treatment guidelines for calciphylaxis, as it poses a challenge due to its diverse clinical presentation and high mortality rate.

Calciphylaxis: Case Presentation and Review of the Literature

BACKGROUND

Calciphylaxis is a potentially life-threatening condition involving painful necrotic skin ulcerations, especially of the lower extremities. It is generally associated with chronic kidney failure but may be seen in nonuremic cases.

CASE REPORT

We report a case of calciphylaxis in a 60-year-old man with diabetes on dialysis for end-stage renal disease and known to have other typical combination of risk factors associated with calciphylaxis syndrome. On examination, he presented with multiple intensely painful calciphylaxis wounds on his legs and ankles. Despite regular wound management of his condition in our ambulatory care setting, his ulcers deteriorated. The patient's pain also increased and he was referred for hospital admission.

CONCLUSION

This case presentation emphasizes the importance of an interdisciplinary team in the treatment of the complex, life-threatening cutaneous manifestations of calciphylaxis. When indicated, prompt referral to a hospital setting is necessary for appropriate care.

Multifactorial aetiology for non-uremic calciphylaxis: a case report

Calciphylaxis is commonly associated with end-stage renal disease patients on haemodialysis. We present a rare case of calciphylaxis in a non-uremic patient. The diagnosis was made clinically and confirmed with skin biopsy showing calcification of the dermal and subcutaneous tissues in the von Kossa stain. We believe that the combination of uncontrolled diabetes mellitus, a non-functioning paraganglioma and vitamin D deficiency in a susceptible female patient was responsible for causing calciphylaxis in our patient. An index of suspicion should be maintained by clinicians for calciphylaxis even in patients without uremia.

Bilateral breast calciphylaxis in a patient who survived earlier extensive tissue necrosis 5 years previously: A case report

INTRODUCTION

Calciphylaxis is a rare condition including patchy dermal necrosis that mostly affects chronic hemodialysis patients. The syndrome usually heralds impending death although patients may survive following a set of measures including an adapted dialysis regimen. The present case is a unique patient who recovered from an earlier episode of upper leg calciphylaxis 5 years previously but developed fatal bilateral breast necrosis.

PRESENTATION OF CASE

A 69 year old Caucasian woman with a history of atrial fibrillation, hypertension, CVA, hyperparathyroidectomy for secondary hyperparathyroidism and end stage renal disease with hemodialysis recovered in 2012 from extensive symptomatic left upper leg necrosis due to calciphylaxis. In 2017, she developed painful, necrotic ulcers on both breasts, again due to calciphylaxis. She had no history of anticoagulants use but she did use prednisolone 5mg/day. She received adequate wound care, pain medication, antibiotics and dialysis frequency was increased with an addition of sodium thiosulfate. A bilateral ablation was discussed but she decided to stop all treatment following pulmonary aspiration and passed away one week later.

DISCUSSION

Calciphylaxis is a rare diagnosis that should be considered in patients with renal insufficiency developing painful patches of skin necrosis.

CONCLUSION

A multidisciplinary treatment approach including hyperparathyroidectomy, modified hemodialysis and wound treatment is recommended. There is limited evidence for surgical intervention.

A 71-Year-Old Female with Myocardial Infarction and Long-Standing Ulcers on the Thigh

Calciphylaxis is most commonly encountered in patients with end-stage renal disease; however, it is increasingly observed in nonuremic patients as well. It is important to consider and diagnose nonuremic calciphylaxis early, as prompt treatment and mitigation of associated risk factors is essential to improve long-term outcomes for these patients. Here, we present the case of a 71-year-old woman with atrial fibrillation on warfarin, but without renal disease, who presented with two long-standing ulcers on her thigh and was diagnosed with the aid of biopsy with calciphylaxis. We review the existing literature on the subject and offer this case as a representative report of a clinicopathologic correlation for this disorder.

Increased Bone Morphogenetic Protein Signaling in the Cutaneous Vasculature of Patients with Calciphylaxis

BACKGROUND

The objective of this study was to investigate the role of bone morphogenetic protein (BMP) signal transduction in the pathogenesis of calciphylaxis.

METHODS

Skin biopsy specimens were obtained from 18 patients with, and 12 patients without, calciphylaxis. Tissue sections were stained with antibodies directed against BMP effector proteins phosphorylated-SMAD (p-SMAD) 1/5/9, inhibitor of DNA 1 (Id1), inhibitor of DNA 3 (Id3), and Runx2. The intensity of staining was scored semi-quantitatively as strong versus weak or absent.

RESULTS

Of the 18 patients with calciphylaxis (mean age: 59 ± 8 years), 9 were women and 15 had end-stage renal disease. Of the 12 control patients (mean age: 57 ± 10 years), 8 were women and 8 had end-stage renal disease. Strong staining for p-SMAD 1/5/9 was detected in blood vessels from all calciphylaxis patients. In 1 patient with calciphylaxis, strong staining for p-SMAD 1/5/9 was detected in a blood vessel that did not have evidence of calcification. Id1 and Id3 immunoreactivity was detected in blood vessels from all 12 patients with calciphylaxis that were tested. Runx2 staining was detected in all 6 patients with calciphylaxis who were tested. p-SMAD 1/5/9 immunoreactivity was weak or absent in blood vessels of 10 of the 12 control samples.

CONCLUSIONS

The BMP signal transduction pathway is activated in the cutaneous vasculature of calciphylaxis patients. The ability to detect p-SMAD 1/5/9, Id1, and Id3 in cutaneous vasculature may assist in the diagnosis of calciphylaxis. As BMP signaling inhibitors become available, this pathway may serve as a future therapeutic target for calciphylaxis.

Clinical Assessment of Warfarin Therapy in Patients with Maintenance Dialysis-Clinical Efficacy, Risks and Development of Calciphylaxis

Recent years, multiple studies regarding clinical efficacy and risks of Warfarin therapy in dialysis patients have been reported, and not a few reports conclude that clinical advantage of Warfarin is questionable in dialysis patients. Conversely, its hemorrhagic risk might be a little more serious in dialysis patients comparing to non-dialysis patients. Basically, it is assumed that long-term administration of Warfarin accelerates the development of vascular athelosclerosis because of the abolished anti-calcification effect of Gla-protein activation by decreased vitamin K activity. This assumption is recently confirmed by multiple reports, suggesting that the Warfarin administration might be worse harmful than ever expected in dialysis patients who are essentially considered to have higher risk of calcification comparing to non-dialysis patients. In addition, it is recently well considered that the Warfarin administration would be a risk factor to cause Warfarin skin necrosis or calciphylaxis, therapy resistant ulcerative skin lesions, which are considered to be highly related to the Warfarin-induced transient hypercoagulable state or acceleration of calcification. Therefore, it is considered that the indication of Warfarin administration to dialysis patients should be carefully assessed. (This is a translation of Jpn J Vasc Surg 2017; 26: 83–90.)

Calciphylaxis: Comparison of radiologic imaging and histopathology

BACKGROUND

The current gold standard for diagnosis of calciphylaxis is a skin biopsy specimen demonstrating calcification of small-caliber arteries or arterioles.

OBJECTIVE

The aim of this study is to compare diameters of calcified vessels seen in skin biopsy specimens and radiology images of patients with calciphylaxis.

METHODS

We conducted a retrospective study of patients with known calciphylaxis from 2009 to 2016 at a community hospital who had both skin biopsy specimens and radiology images taken as part of their routine care. Vascular calcification was compared in skin biopsy specimens and radiology images.

RESULTS

Seven patients were identified. Small-vessel calcification as fine as 0.1 to 0.3 mm was identified on plain films in 3 patients; 0.1 to 0.2 mm by mammography in 3 patients, and 0.1 to 0.2 mm by computed tomography imaging in 1 patient, nearly as fine a resolution as on histopathology.

LIMITATIONS

This was a single-center study with limited sample size.

CONCLUSION

Radiologic imaging might enable more rapid diagnosis of calciphylaxis when skin biopsy specimen is pending or not available.

Ecto-5' -Nucleotidase CD73 (NT5E), vitamin D receptor and FGF23 gene polymorphisms may play a role in the development of calcific uremic arteriolopathy in dialysis patients - Data from the German Calciphylaxis Registry

Introduction

Calciphylaxis/calcific uremic arteriolopathy affects mainly end-stage kidney disease patients but is also associated with malignant disorders such as myeloma, melanoma and breast cancer. Genetic risk factors of calciphylaxis have never been studied before.

Methods

We investigated 10 target genes using a tagging SNP approach: the genes encoding CD73/ ecto-5'-nucleotidase (purinergic pathway), Matrix Gla protein, Fetuin A, Bone Gla protein, VKORC1 (all related to intrinsic calcification inhibition), calcium-sensing receptor, FGF23, Klotho, vitamin D receptor, stanniocalcin 1 (all related to CKD-MBD). 144 dialysis patients from the German calciphylaxis registry were compared with 370 dialysis patients without history of CUA. Genotyping was performed using iPLEX Gold MassARRAY(Sequenom, San Diego, USA), KASP genotyping chemistry (LGC, Teddington, Middlesex, UK) or sequencing. Statistical analysis comprised logistic regression analysis with adjustment for age and sex.

Results

165 SNPs were finally analyzed and 6 SNPs were associated with higher probability for calciphylaxis (OR>1) in our cohort. Nine SNPs of three genes (CD73, FGF23 and Vitamin D receptor) reached nominal significance (p< 0.05), but did not reach statistical significance after correction for multiple testing. Of the CD73 gene, rs4431401 (OR = 1.71, 95%CI 1.08–2.17, p = 0.023) and rs9444348 (OR = 1.48, 95% CI 1.11–1.97, p = 0.008) were associated with a higher probability for CUA. Of the FGF23 and VDR genes, rs7310492, rs11063118, rs13312747 and rs17882106 were associated with a higher probability for CUA.

Conclusion

Polymorphisms in the genes encoding CD73, vitamin D receptor and FGF23 may play a role in calciphylaxis development. Although our study is the largest genetic study on calciphylaxis, it is limited by the low sample sizes. It therefore requires replication in other cohorts if available.

A case of calciphylaxis in a patient with hypoparathyroidism and normal renal function

OBJECTIVE

To present the case of a patient with a history of thyroid cancer, postsurgical hypoparathyroidism, chronic calcitriol use, and normal renal function who presented with painful skin lesions secondary to calciphylaxis.

METHODS

We describe the history, biochemistry, histopathology, evaluation, and management of this patient.

RESULTS

A 47-year-old female with hypoparathyroidism, chronically treated with calcitriol and calcium, presented with exquisitely painful skin ulcerations. Four months prior to the onset of symptoms, she had initiated warfarin therapy for atrial fibrillation. Review of laboratory data from the past year revealed elevated calcium and phosphorus levels. A diagnosis of calciphylaxis was made based upon pathologic evaluation of a skin biopsy. Management included titration of calcitriol and calcium to maintain serum calcium and phosphate levels in the low-normal range. Sodium thiosulfate was administered at a dose of 25 mg intravenously 3 times a week with some resolution in the patient's pain. Unfortunately, the patient battled recurrent bacteremia and sepsis, presumably related to her calciphylaxis wounds, and ultimately succumbed to complications from sepsis.

CONCLUSION

Although calciphylaxis is typically associated with renal insufficiency and secondary hyperparathyroidism, we highlight the case of a patient with normal renal function and hypoparathyroidism. Patients treated with chronic calcitriol should have serum calcium and phosphorus monitored closely and may benefit from non-calcium-based phosphate binders if hyperphosphatemia becomes unavoidable. This is especially important in the presence of other risk factors for calciphylaxis, including warfarin use.

Cardiovascular calcifications in chronic kidney disease: Potential therapeutic implications

Cardiovascular (CV) calcification is a highly prevalent condition at all stages of chronic kidney disease (CKD) and is directly associated with increased CV and global morbidity and mortality. In the first part of this review, we have shown that CV calcifications represent an important part of the CKD-MBD complex and are a superior predictor of clinical outcomes in our patients. However, it is also necessary to demonstrate that CV calcification is a modifiable risk factor including the possibility of decreasing (or at least not aggravating) its progression with iatrogenic manoeuvres. Although, strictly speaking, only circumstantial evidence is available, it is known that certain drugs may modify the progression of CV calcifications, even though a direct causal link with improved survival has not been demonstrated. For example, non-calcium-based phosphate binders demonstrated the ability to attenuate the progression of CV calcification compared with the liberal use of calcium-based phosphate binders in several randomised clinical trials. Moreover, although only in experimental conditions, selective activators of the vitamin D receptor seem to have a wider therapeutic margin against CV calcification. Finally, calcimimetics seem to attenuate the progression of CV calcification in dialysis patients. While new therapeutic strategies are being developed (i.e. vitamin K, SNF472, etc.), we suggest that the evaluation of CV calcifications could be a diagnostic tool used by nephrologists to personalise their therapeutic decisions.

Multidisciplinary approach to calcific uremic arteriolopathy

PURPOSE OF REVIEW

Calcific uremic arteriolopathy (CUA), as known as calciphylaxis, is a rare and poorly understood disease seen predominantly in end stage renal disease patients. A collaborative multidisciplinary approach to develop and implement treatment and prevention methods is described.

RECENT FINDINGS

Overall, the scientific literature on CUA is largely restricted to case reports and case series. Recent reports indicate that the incidence of CUA may be on the rise and emphasize an association with vitamin K antagonist therapy, obesity, and diabetes mellitus. Serum calcium, phosphorous, and parathyroid hormone levels have been reported to be quite variable in patients with CUA and may reflect the heterogeneity of study designs. A multidisciplinary and multimodal approach that incorporates wound and pain management, sodium thiosulfate, optimization of mineral bone parameters, bisphosphonates, and avoidance of risk factors such as vitamin K antagonist has been advocated in the latest reports. Sodium thiosulfate although used frequently to treat CUA has unclear efficacy requiring further examination.

SUMMARY

This review describes the recent literature in the field of CUA including its limitations. It provides a summary of a multidisciplinary approach to CUA management.

Successful Treatment of Lung Calciphylaxis With Sodium Thiosulfate in a Patient With Sickle Cell Disease: A Case Report

Calciphylaxis is a small vessel vasculopathy, characterized by medial wall calcification that develops in a few patients with chronic renal failure. The prognosis of skin calciphylaxis has improved considerably since the introduction of sodium thiosulfate (STS), but it remains unclear whether this therapy is effective against organ lesions related to calciphylaxis. Pulmonary calciphylaxis is a usually fatal medical condition that may occur in association with skin involvement in patients with end-stage renal disease.We report here the case of a 49-year-old woman homozygous sickle cell disease patient on chronic hemodialysis with biopsy-proven systemic calciphylaxis involving the lungs and skin. On admission, ulcerative skin lesions on the lower limbs and bilateral pulmonary infiltrates on chest computerized tomography scan were the main clinical and radiological findings. Skin and bronchial biopsies demonstrated calciphylaxis lesions. The intravenous administration of STS in association with cinacalcet for 8 consecutive months led to a clear improvement in skin lesions and thoracic lesions on chest computerized tomography scan.This case suggests for the first time that organ lesions related to calciphylaxis, and particularly lung injury, are potentially reversible. This improvement probably resulted from the combination of 3 interventions (more frequent dialysis, cinacalcet, and STS), rather than the administration of STS alone.

Calcific uraemic arteriolopathy

A 37-year-old African-American woman with end-stage renal disease presumed to be secondary to diabetes mellitus type 2, on daily peritoneal dialysis, was admitted for a painful left lower extremity lesion. Examination revealed a large, dusky, tender region over the left lateral thigh. She was on warfarin for mechanical heart valves. Despite discontinuation of warfarin and placement on heparin, the lesion progressed to extend to the medial left thigh and medial and lateral right thigh. CT scan demonstrated arteriolar medial calcification and vascular calcification of the small subcutaneous vessels, without evidence of abscess or haematoma. The patient declined punch biopsy. Given the known risk factors of high calcium-phosphate and radiological findings, a diagnosis of calcific uraemic arteriolopathy was made. Phosphate-binder therapy was optimised. She was transitioned to daily haemodialysis, and sodium thiosulfate was initiated. Skin lesions demonstrated improvement at her 5 weeks posthospitalisation follow-up.

Integrated image data and medical record management for rare disease registries. A general framework and its instantiation to theGerman Calciphylaxis Registry

Especially for investigator-initiated research at universities and academic institutions, Internet-based rare disease registries (RDR) are required that integrate electronic data capture (EDC) with automatic image analysis or manual image annotation. We propose a modular framework merging alpha-numerical and binary data capture. In concordance with the Office of Rare Diseases Research recommendations, a requirement analysis was performed based on several RDR databases currently hosted at Uniklinik RWTH Aachen, Germany. With respect to the study management tool that is already successfully operating at the Clinical Trial Center Aachen, the Google Web Toolkit was chosen with Hibernate and Gilead connecting a MySQL database management system. Image and signal data integration and processing is supported by Apache Commons FileUpload-Library and ImageJ-based Java code, respectively. As a proof of concept, the framework is instantiated to the German Calciphylaxis Registry. The framework is composed of five mandatory core modules: (1) Data Core, (2) EDC, (3) Access Control, (4) Audit Trail, and (5) Terminology as well as six optional modules: (6) Binary Large Object (BLOB), (7) BLOB Analysis, (8) Standard Operation Procedure, (9) Communication, (10) Pseudonymization, and (11) Biorepository. Modules 1-7 are implemented in the German Calciphylaxis Registry. The proposed RDR framework is easily instantiated and directly integrates image management and analysis. As open source software, it may assist improved data collection and analysis of rare diseases in near future.

Blueprint for a European calciphylaxis registry initiative: the European Calciphylaxis Network (EuCalNet)

Calcific uraemic arteriolopathy (CUA) is a rare disease and continues to be a clinical challenge. The typical course of CUA is characterized by painful skin discolouration and induration evolving to necrotic ulcerations. Medial calcification of cutaneous arterioles and extensive extracellular matrix remodelling are the hallmarks of CUA. The epidemiology and risk factors associated with this disease are still not fully understood. Moreover, CUA treatment strategies vary significantly among centres and expert recommendations are heterogeneous. Registries may provide important insights and information to increase our knowledge about epidemiology and clinical aspects of CUA and may help to optimize its therapeutic management. In 2006, we established an internet-based registry in Germany (www.calciphylaxie.de) to allow online notification of patients with established or suspected CUA. The registry includes a comprehensive database with questions covering >70 parameters and items regarding patient-related and laboratory data, clinical background and presentation as well as therapeutic strategies. The next phase will be to allow international patient registration via www.calciphylaxis.net as part of the multinational EuCalNet (European Calciphylaxis Network) initiative, which is supported by the ERA-EDTA scientific working group ‘CKD-MBD’. Based on the valuable experience with the previous German CUA registry, EuCalNet will be a useful tool to collect data on the rare disease CUA and may become a basis for prospective controlled trials in the near future.

[The matrix-gla protein awakening may lead to the demise of vascular calcification]

Matrix-gla-protein (MGP) is mainly secreted by chondrocytes and smooth vascular muscle cells. This potent inhibitor of vascular calcification need to undergo 2 post-transcriptional steps to be fully active: one phosphorylation of 3 serine residues (on 5) and a carboxylation of 5 glutamate residues (on 9). Like other "Gla" proteins, this carboxylation is vitamin K dependant. Several forms of MGP thus circulate in the plasma, some of them being totally inactive (the unphosphorylated and uncarboxylated MGP), some others being partially or fully active, according to the number of phosphorylated or carboxylated sites. A theoretical link exists between MGP, vitamin K, vascular calcifications and cardiovascular diseases. This link is even more evident in patients suffering from chronic kidney diseases (CKD), and notably hemodialysis patients. If this link has been demonstrated in different experimental studies, clinical studies are mainly observational and their results must be interpreted accordingly. MGP concentrations are definitely not yet a surrogate to estimate the levels of vascular calcification, but could allow the monitoring of vitamin K treatment. Modulation of MGP concentrations may reduce vascular calcification in hemodialyzed patients, if the large ongoing trials show an efficiency of this treatment. In this review, we will summarize the role of MGP in the vascular calcifications process, describe the problems linked to the analytical determination of MGP in plasma and finally describe the different clinical studies on MGP and vascular calcifications in the general population and in CKD patients.

Calciphylaxis: risk factors, diagnosis, and treatment

Calciphylaxis is a rare but devastating condition that has continued to challenge the medical community since its early descriptions in the scientific literature many decades ago. It is predominantly seen in patients with chronic kidney failure treated with dialysis (uremic calciphylaxis) but is also described in patients with earlier stages of chronic kidney disease and with normal kidney function. In this review, we discuss the available medical literature regarding risk factors, diagnosis, and treatment of both uremic and nonuremic calciphylaxis. High-quality evidence for the evaluation and management of calciphylaxis is lacking at this time due to its rare incidence and poorly understood pathogenesis and the relative paucity of collaborative research efforts. We hereby provide a summary of recommendations developed by a multidisciplinary team for patients with calciphylaxis.

Calciphylaxis: from the disease to the diseased

Calciphylaxis, or calcific uremic arteriolopathy, is a vascular ossification-calcification disease involving cutaneous or visceral arterioles, with ischemic damage of the surrounding tissues, usually in the setting of chronic kidney disease. Pathogenesis is still unclear and probably comprises the participation of vascular smooth muscle cells, endothelial cells and macrophages surrounded by a uremic and/or pro-calcifying environment. According to the original concept of calcific uremic arteriolopathy coined by Hans Selye, risk factors may be divided into sensitizers and challengers and their knowledge is useful in clinical practice to pre-emptively identify both uremic and non-uremic 'at risk' patients and guide treatment. Systemic calcific uremic arteriolopathy is a rarity. Cutaneous calcific uremic arteriolopathy is more frequent and clinically presents as a first phase of cutaneous hardening and erythema, followed by a second phase of ulcerations and scars; these two phases are probably associated with the initial development of arteriolar lesion and tissue ischemic damage, respectively. Clinical history, physical examination, laboratory analysis, histology and imaging are the main tools to exclude important differential diagnoses and obtain a definitive diagnosis. Treatment is generally unrewarding and consists of rigorous control of comorbid conditions, anti-oxidant, anti-inflammatory and antithrombotic strategies, avoidance of iatrogeny and wound and pain management. Prognosis remains poor in terms of morbidity and mortality. Efforts should be made towards a greater awareness of calcific uremic arteriolopathy, development of better therapies and improvement of clinical outcomes.

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.

Dephosphorylated-uncarboxylated Matrix Gla protein concentration is predictive of vitamin K status and is correlated with vascular calcification in a cohort of hemodialysis patients

BACKGROUND

Matrix Gla protein (MGP) is known to act as a potent local inhibitor of vascular calcifications. However, in order to be active, MGP must be phosphorylated and carboxylated, with this last process being dependent on vitamin K. The present study focused on the inactive form of MGP (dephosphorylated and uncarboxylated: dp-ucMGP) in a population of hemodialyzed (HD) patients. Results found in subjects being treated or not with vitamin K antagonist (VKA) were compared and the relationship between dp-ucMGP levels and the vascular calcification score were assessed.

METHODS

One hundred sixty prevalent HD patients were enrolled into this observational cohort study, including 23 who were receiving VKA treatment. The calcification score was determined (using the Kauppila method) and dp-ucMGP levels were measured using the automated iSYS method.

RESULTS

dp-ucMGP levels were much higher in patients being treated with VKA and little overlap was found with those not being treated (5604 [3758; 7836] vs. 1939 [1419; 2841] pmol/L, p < 0.0001). In multivariate analysis, treatment with VKA was the most important variable explaining variation in dp-ucMGP levels even when adjusting for all other significant variables. In the 137 untreated patients, dp-ucMGP levels were significantly (p < 0.05) associated both in the uni- and multivariate analysis with age, body mass index, plasma levels of albumin, C-reactive protein, and FGF-23, and the vascular calcification score.

CONCLUSION

We confirmed that the concentration of dp-ucMGP was higher in HD patients being treated with VKA. We observed a significant correlation between dp-ucMGP concentration and the calcification score. Our data support the theoretical role of MGP in the development of vascular calcifications. We confirmed the potential role of the inactive form of MGP in assessing the vitamin K status of the HD patients.

TRIAL REGISTRATION

B707201215885.

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: a rare but potentially fatal event of chronic kidney disease. Case report

Calciphylaxis or calcific uremic arteriolopathy is a rare cutaneous-systemic disease occurring in patients with advanced chronic kidney disease. The classical clinical picture is that of a necrotic and progressive skin ulcer of reticular pattern, mostly in the lower legs and susceptible to local infection. It is a product of mural calcification and occlusion of cutaneous and sub-cutaneous arteries and arterioles. The authors report the case of a 73-year-old male patient in his late stage of renal disease presenting severe necrotic cutaneous ulcers on lower legs followed by local and systemic infection and death due to sepse after parathyroidectomy.

Calciphylaxis: a rare but fatal delayed complication of Roux-en-Y gastric bypass surgery

Gastric bypass is a commonly used surgical procedure that has shown impressive health benefits for patients with morbid obesity. However, mineral bone abnormalities (hypocalcemia, hypovitaminosis D, and secondary hyperparathyroidism) and micronutrient (e.g., iron) deficiencies are common complications after gastric bypass surgery due to alterations in the digestive anatomy. These abnormalities, their treatments, and a number of other factors associated with obesity can set up a perfect storm to induce calciphylaxis, a rare but highly fatal condition with severe comorbid conditions. We present a fatal case of nonuremic calciphylaxis coincident with symptomatic hypocalcemia in a morbidly obese man with a history of Roux-en-Y gastric bypass surgery.

Extraosseous calcification in end-stage renal disease: from visceral organs to vasculature

In earlier days, periarticular accumulations of calcium phosphate causing tumor-like depositions were considered the result of passive precipitation and referred to as metastatic calcifications. From sophisticated computer tomographic studies and growing insight, we have learned that calcifications in the cardiovascular system are far more threatening and in fact one of the most important sequela of end-stage renal disease. The histologic characteristic of uremia-related calcification is arteriosclerosis of the media. In addition, there is atherosclerosis of the intima, due to the high prevalence of classic cardiovascular risk factors in renal disease. The two vascular features can frequently exist at different sites in the vasculature. Novel diagnostic techniques are helping to elucidate the pathogenetic mechanisms of active conversion of vascular smooth muscle cells to osteochondritic cells. Through this process, extensive calcification of the central and peripheral vasculature ensues, influenced by different promotors and inhibitors. Calciphylaxis is a special form of extraosseous calcification leading to skin necrosis. The factors that trigger the development of calciphylaxis are not completely understood, but this syndrome shares part of the pathophysiologic basis of extraosseous calcification in general. However, the therapeutic approach must be prompt and aggressive, because of the poor prognosis. Frequently, a fatal outcome cannot be avoided in calciphylaxis.

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.

Warfarin-induced calciphylaxis: a case report and review of literature

Calciphylaxis is a challenging complication of end-stage renal disease, with an unknown underlying mechanism. Several risk factors have been identified, such as hyperphosphatemia, hypercalcemia, hyperparathyroidism, low serum albumin levels, and history of warfarin therapy. This article presents a case of calciphylaxis provoked by reintroduction of warfarin therapy, introducing the possibility of direct induction.

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.

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.