Calciphylaxis in end-stage kidney disease: outcome data from the United Kingdom Calciphylaxis Study

Characteristics and prognostic values of abdominal aortic branches calcification in hemodialysis patients

BACKGROUND

Vascular calcification is highly prevalent and associated with mortality in hemodialysis patients. However, extreme splanchnic arterial calcification in calciphylaxis with poor prognosis raises questions regarding the reliability of previous vascular calcification scoring methods. Therefore, this study aimed to examine the distribution characteristics of abdominal aortic branch calcification and identify a more reliable predictor of mortality in hemodialysis patients.

METHODS

The cohort study included 237 hemodialysis patients. The distribution characteristics of abdominal aortic branch calcification were determined by quantifying the calcification volumes. The primary and secondary outcomes were all-cause mortality and new-onset cardiovascular events, respectively. We compared the prognostic values of abdominal aortic branch calcification and constructed a predictive nomogram model.

RESULTS

The prevalence of abdominal vascular calcification in hemodialysis patients was 95.36%, with the highest prevalence in the abdominal aorta (88.61%) and internal iliac artery (85.65%). During a median follow-up period of 3.92 years, 137 patients died. Internal iliac artery and mesenteric artery calcification showed the greatest predictive values for mortality. Internal iliac artery calcification and serum albumin level were independently associated with mortality in hemodialysis patients (p < .001). The nomogram model constructed with internal iliac artery calcification, serum albumin level, age, and comorbid cardiovascular disease was well discriminative, calibrated, and clinically applicable for predicting 3-year survival.

CONCLUSION

Abdominal aortic branch calcification, particularly internal iliac artery calcification, is a preferable prognostic predictor than abdominal aorta or coronary artery calcification in hemodialysis patients.

Calciphylaxis Following Parathyroidectomy in Chronic Kidney Disease Patients-Case Report and Literature Review

Calcific uremic arteriolopathy, also known as calciphylaxis, is a rare and often fatal condition most commonly occurring in patients with end-stage renal disease (ESRD). It is marked by extensive vascular calcification, resulting in tissue ischemia and the development of distinctive skin lesions. We report the case of a 38-year-old male with ESRD due to polycystic kidney disease, who developed calciphylaxis lesions following total parathyroidectomy (PTx). We also performed an electronic search of PubMed and Google Scholar from inception until December 2024, using the following keywords: 'chronic kidney disease', 'dialysis', 'calciphylaxis', 'calcific uremic arteriolopathy', 'secondary hyperparathyroidism', and 'parathyroidectomy'. A literature review of calciphylaxis cases following PTx in chronic kidney disease (CKD) patients identified 14 cases reported up to the manuscript's writing. Although PTx can be a treatment option for calciphylaxis related to severe secondary hyperparathyroidism (SHPT), leading to clinical improvement in some patients, there are atypical calciphylaxis cases occurring after PTx. While the mechanism is not fully understood, the sudden reduction in parathormone (PTH) levels leading to hypocalcemia and decreased bone turnover, together with an increased calcium loading in a patient at risk for abnormal mineralization, may promote vascular and soft tissue calcification. However, the long-term impact of severe SHPT with a delayed post-PTx manifestation cannot be ruled out. Clinicians should consider calciphylaxis in CKD patients with new painful skin lesions. Skin biopsy remains controversial, but a thorough clinical examination, and, in some cases, imaging are essential for a correct diagnosis. A multidisciplinary, personalized approach is crucial, with careful management of post-PTx hypocalcemia and calcium supplementation. Further research is needed to enhance understanding and treatment strategies.

Risk Factors Associated With the Development of Calciphylaxis in Patients With Chronic Kidney Disease: A Systematic Review

Calciphylaxis is a rare but potentially life-threatening disease that is not yet completely understood. It occurs mainly in patients with chronic kidney disease termed calcific uremic arteriolopathy (CUA) but also affects patients with normal renal function. Although this disease's pathogenesis is unclear, it is associated with the dysregulation of calcium and phosphate and subsequent calcification of peripheral arterioles. Calciphylaxis has up to 80% mortality, even with multidisciplinary and multimodal treatment modalities. The available literature identified some relevant risk factors associated with the development of calciphylaxis, but the authors differ significantly in risk profiling. Moreover, most papers on calciphylaxis are observational studies, namely case series, case reports, cohort, and cross-sectional studies. Although recently available articles mentioned some risk factors, the studies mainly focused on diagnosis, treatment, and prognosis with limited emphasis on structured risk profiling. In addition, experimental and systemic review studies on risk factors associated with calciphylaxis are lacking. Thus, this systematic review's primary focus is to determine risk factors associated with developing calciphylaxis in patients with chronic kidney disease. We searched electronic databases from 2018 to 2024 for articles that contained relevant risk factors linked with the development of calciphylaxis using the keywords calciphylaxis, chronic kidney disease, and risk factors. We identified 486 articles, removed duplicate papers from selected articles, applied inclusion and exclusion criteria, and conducted a quality assessment test. Two independent authors performed data extraction manually, and we compared the results for consistency and accuracy. Twenty-two articles met the eligibility criteria, but only 16 articles passed the quality assessment appraisal and were included in the systematic review. We identified 1,739 patients: 664 (38.2%) and 1075 (61.81%) were males and females, respectively. A total of 1373 (78.95%) were on dialysis, and 926 (53.25%) were diabetics. Caucasians and patients with obesity were 695 (37.90%) and 613 (35.25%), respectively. At the time of diagnosis, 599 (34.45%), 311 (17.90%), and 278 (15.99%) were on vitamin K antagonists (VKA), vitamin D, and calcium phosphate binders. The number of patients with elevated parathyroid hormone was 196 (11.27%). Our study found no experimental or systematic reviews that primarily focused on risk factors associated with the development of calciphylaxis. Our research indicated that dialysis is the most frequent risk factor linked to the development of calciphylaxis. Other risk factors include being caucasian, female gender, obese, diabetic mellitus (DM), having elevated parathyroid hormone, and use of VKA (warfarin), vitamin D, and calcium phosphate binders. These findings are consistent with the evidence seen in most of the articles we reviewed. However, the papers we studied are mainly observational mono-centered research articles, with the majority having a small sample size. Thus, we recommend a multicenter, large-scale experimental study to assess risk factors and profiling for the development of calciphylaxis in patients with chronic kidney disease.

Assessment of diagnostic delay, morbidity, and mortality outcomes in 302 calciphylaxis patients over a 17-year period: A retrospective cohort study

BACKGROUND

Calciphylaxis patients historically have experienced diagnostic challenges and high morbidity; however limited data is available examining these characteristics over time.

OBJECTIVE

The primary goals were to a) investigate factors associated with diagnostic delay of calciphylaxis and b) assess morbidity outcomes. The secondary goal was to provide updated mortality rates.

METHODS

A retrospective review of 302 adult patients diagnosed with calciphylaxis between January 1, 2006 and December 31, 2022 was conducted. Univariate and multivariate statistical analyses were performed.

RESULTS

Nonnephrogenic calciphylaxis (P = .0004) and involvement of the fingers (P = .0001) were significantly associated with an increased diagnostic delay, whereas involvement of the arms (P = .01) and genitalia (P = .022) resulted in fewer days to diagnosis. Almost all patients with genitalia, finger, or toe involvement had nephrogenic disease. The number of complications per patient decreased with time, especially for wound infections (P = .028), increase in lesion number (P = .012), and recurrent hospitalizations (P = .020). Updated 1-year mortality rates were 36.70% and 30.77% for nephrogenic and nonnephrogenic calciphylaxis, respectively.

LIMITATIONS

Limitations include the retrospective nature and data from a single institution.

CONCLUSION

Diagnostic delay, particularly in nonnephrogenic calciphylaxis, and complications per patient decreased with time, highlighting the importance of continued awareness to expedite diagnosis. Mortality rates have continued to improve in recent years.

Calciphylaxis Episodes in the Australia and New Zealand Dialysis and Transplant Registry

Introduction

Calciphylaxis is a rare disorder associated with significant morbidity and mortality. Data registries are an invaluable source of information for rare diseases. We reviewed cases of calciphylaxis recorded in the Australia and New Zealand Dialysis and Transplant Registry (ANZDATA) and evaluated associations and outcomes of this condition.

Methods

Data was obtained on all cases of calciphylaxis reported between 2019 and 2022 in Australian and New Zealand patients on kidney replacement therapy (KRT). This cohort was compared to all patients in the registry who received KRT from 2019 to 2022 without an episode of calciphylaxis. Cox proportional hazards regression including a time-varying covariate for calciphylaxis episode was conducted for mortality with models restricted to patients on dialysis only.

Results

From 2019 to 2022, 333 patients had calciphylaxis episodes reported. Overall incidence rate for patients on dialysis was 4.5 (4.1-5.1) episodes per 1000 patient-years on dialysis. Median age was 63 (interquartile range [IQR]: 55-73) years, 54% were female, 66% had diabetes, 59% were obese (body mass index [BMI] ≥ 30 kg/m2) and 77% were receiving hemodialysis (HD) treatment. Compared to patients without calciphylaxis (n = 46,526), patients with calciphylaxis were more likely to be older, female, and have diabetes, greater BMI, coronary artery, and peripheral vascular disease. The median time to calciphylaxis was 3.2 (IQR: 0.9-6.7) years after KRT commencement. Half of the patients with calciphylaxis died by 12 months from diagnosis. Adjusted hazard ratio (HR) of mortality for patients on dialysis with calciphylaxis <1 year and 1 to 4 years after an episode was 5.8 (4.9-6.9) and 1.5 (1.0-2.1), respectively compared to patients on dialysis without calciphylaxis.

Conclusion

Calciphylaxis is a rare but life-threatening condition in people on KRT with the greatest mortality burden within 12 months of diagnosis.

Calciphylaxis in a patient with hypoparathyroidism and MEN-1 syndrome

Summary

Calciphylaxis is a rare disorder characterised by the development of painful necrotic skin lesions. Occlusion of cutaneous arterioles due to ectopic calcification leads to potentially life-threatening widespread skin loss. Most cases occur in patients with chronic renal disease, which leads to dysregulation of calcium and phosphate homeostasis. Only a handful of case reports exist describing calciphylaxis occurring in patients without chronic renal disease but with hypoparathyroidism. We report on a unique case of a 53-year-old man with multiple endocrine neoplasia type 1 syndrome and acquired hypoparathyroidism due to total parathyroidectomy who went on to develop calciphylaxis following cardiac surgery.

Learning points

Calciphylaxis most commonly occurs in the context of chronic renal disease but can rarely occur in its absence as a consequence of calcium and phosphate dysregulation. Patients who develop necrotic skin lesions in the presence of hypoparathyroidism require an urgent dermatological opinion. Mortality from calciphylaxis is high, with the majority of deaths occurring secondary to sepsis. Management of calciphylaxis requires a multidisciplinary team approach to manage wound healing, infections and pain. Recovery with full rehabilitation from calciphylaxis can take months to years.

Successful treatment of severe calciphylaxis in a renal transplant patient with previous total parathyroidectomy

Calciphylaxis is a rare dermatological condition strongly associated with chronic kidney disease. The pathophysiology and optimum treatment remain uncertain. Calciphylaxis is known mostly to affect dialysis patients but is less frequently reported in renal transplant recipients. We report the case of a renal transplant recipient who had undergone previous total parathyroidectomy.

Atrial Fibrillation in Kidney Failure: Challenges in Risk Assessment and Anticoagulation Management

Management of atrial fibrillation (AF) is a clinical conundrum in people with kidney failure. Stroke risk is disproportionately high, but clinicians have a limited armamentarium to improve outcomes in this population in whom there is a concurrently high bleeding risk. Direct oral anticoagulants may have a superior benefit-risk profile compared with vitamin K antagonists in people on hemodialysis. Although research has predominantly focused on identifying a safe and effective oral anticoagulation option to reduce stroke risk in people with kidney failure (and predominantly those on hemodialysis), it remains uncertain how clinicians discriminate between people who would derive net clinical benefit as opposed to net harm. The recommended CHA2DS2-VASc score cutoffs provide poor discriminatory value, and there is an urgent need to identify robust markers of thromboembolic risk in kidney failure. There is increasing data to challenge the prior dogma of risk equivalence across AF type, and the American Heart Association highlights moving beyond AF as a binary entity to consider the prognostic significance of AF burden. Implantable cardiac monitor studies reveal high rates and varied burden of subclinical and paroxysmal AF in people on hemodialysis. The association between AF burden and the proarrhythmic environment of hemodialysis with cyclical volume loading, offloading, and electrolyte changes is not well studied. We review the significance of AF burden as a contributor to thromboembolic risk, its potential as the missing link in risk assessment, and updated evidence for anticoagulation in people with kidney failure.

Calcific uraemic arteriolopathy presenting as cellulitis of the dorsal foot

Calcific uraemic arteriolopathy (CUA) is a rare and poorly understood entity that typically presents with painful lesions affecting adipose-rich areas of the lower extremities. We report an unusual case of CUA presenting as presumed cellulitis of the dorsal surface of the distal lower extremity with acute development of a bullous lesion. As CUA incidence is predicted to increase due to its relationship with end-stage renal disease, recognising the full clinical spectrum of this disease is essential to promote further understanding of this disorder and exploration of additional therapeutics to limit disease morbidity and mortality.

Clinical features and outcomes of calciphylaxis in Chinese patients with chronic kidney disease

AIM

Calciphylaxis is a rare disease, predominantly in chronic kidney disease (CKD), characterized by high morbidity and mortality. Data from the Chinese population have been an invaluable resource for a better understanding of natural history, optimal treatments and outcomes of calciphylaxis.

METHODS

A retrospective study was conducted in 51 Chinese patients diagnosed with calciphylaxis at Zhong Da Hospital affiliated to Southeast University from December 2015 to September 2020.

RESULTS

Between 2015 and 2020, 51 cases of calciphylaxis were registered in The China Calciphylaxis Registry (http://www.calciphylaxis.com.cn), which was developed by Zhong Da Hospital. The mean age of the cohort was 52.02 ± 14.09 years, and 37.3% were female. Forty-three patients (84.3%) were on haemodialysis, with a median dialysis vintage of 88 months. Eighteen patients (35.3%) had a resolution of calciphylaxis and 20 patients (39.2%) died. Patients in later stages had higher overall mortality than those in earlier stages. Delay from skin lesions onset to diagnosis and calciphylaxis-related infections were risk factors in both early and overall mortality. Additionally, dialysis vintage and infections were significant risk factors in calciphylaxis-specific mortality. Among therapeutic strategies, only the use of sodium thiosulfate (STS) ≥3 courses (14 injections) was significantly associated with decreased hazard of death in both early and overall mortality.

CONCLUSION

For Chinese patients with calciphylaxis, delay from skin lesions onset to diagnosis and infections secondary to wounds are risk factors for the prognosis of patients with calciphylaxis. Additionally, patients in earlier stages have better survival and early continuous use of STS is highly suggested.

[Surgery of hyperparathyroidism]

The surgical removal of diseased parathyroid glands is the only curative treatment for primary and secondary hyperparathyroidism. Before an intervention, the confirmed diagnosis and an accurate localization are decisive for selection of the appropriate procedure. After appropriate localization diagnostics, a focussed intervention is possible for primary hyperparathyroidism, whereby every intervention must be controlled by intraoperative monitoring of parathyroid hormone. Reoperations or multiple glandular disease necessitate a differentiated approach with appropriate prior diagnostics.

An Intensive Multidisciplinary Approach in Management of Extensive Nonuremic Calciphylaxis of the Bilateral Lower Extremities with Angioinvasive Fungus and Mold

Management of infected wounds related to calciphylaxis poses a significant clinical challenge with high morbidity and mortality. Given no definitive management guidelines exist specific to nonuremic calciphylaxis, multiple modalities including sodium thiosulfate, antibiotics, hyperbaric oxygen therapy, and surgical debridement with wound care must be considered. When occurring over a large surface area, standard daily dressing changes are especially labor intensive, inefficient, and ineffective. Negative pressure wound therapy with instillation and dwell time offers broad wound coverage with ongoing therapeutic benefit. We present the case of a previously healthy 19-year-old woman who was transferred for tertiary level care of extensive nonuremic calciphylaxis wounds of the bilateral lower extremities complicated by angioinvasive coinfection with fungus and mold that was managed with a multidisciplinary approach of intensive medical management, aggressive surgical debridement, and negative pressure wound therapy with instillation of hypochlorous acid solution. Ultimately, she achieved full granulation and wound coverage with skin grafting. Large area, infected wounds related to nonuremic calciphylaxis can be successfully managed with multidisciplinary medical management, aggressive surgical debridement, and negative pressure wound therapy that can instill and dwell hypochlorous acid solution.

The Role of Iron in Calciphylaxis—A Current Review

Calcific uraemic arteriolopathy (CUA), also known as calciphylaxis, is a rare and often fatal condition, frequently diagnosed in end-stage renal disease (ESRD) patients. Although exact pathogenesis remains unclear, iron supplementation is suggested as a potential risk factor. Iron and erythropoietin are the main stay of treatment for anaemia in ESRD patients. Few observational studies support the role of iron in the pathogenesis of calciphylaxis although data from the pivotal trial was not strongly supportive of this argument, i.e., no difference in incidence of calciphylaxis between the low-dose and high-dose iron treatment arms. Elevated levels of vascular cell adhesion molecules in association with iron excess were postulated to the pathogenesis of CUA by causing inflammation and calcification within the microvasculature. In-addition, oxidative stress generated because of iron deposition in cases of systemic inflammation, such as those seen in ESRD, may play a role in vascular calcification. Despite these arguments, a direct correlation between cumulative iron exposure with CUA incidence is not clearly demonstrated in the literature. Consequently, we do not have evidence to recommend iron reduction or cessation in ESRD patients that develop CUA.

A Rare Presentation of Penile Calciphylaxis Requiring Partial Penectomy

Calciphylaxis is a rare disease and carries high morbidity and mortality rates. It’s characterized by microvascular calcification and occlusion, which leads to a life-threatening disease characterized by skin necrosis and ulceration. Calciphylaxis is classified as uremic, which occurs in patients with end-stage renal disease and who are non-uremic. Non-uremic calciphylaxis is an even rarer disease that occurs in patients without end-stage renal disease and has a high mortality rate secondary to sepsis. The most common risk factors are diabetes mellitus, hyperparathyroidism, malignant neoplasm, warfarin-based anticoagulation, alcoholic liver disease, and autoimmune disorders. The management includes wound debridement, pain management, and sepsis control.

We report a case of penile calciphylaxis in a 36-year-old male with a 15-year history of type II diabetes mellitus and chronic kidney disease. He presented with penile ulceration, which rapidly progressed to necrosis. He also had skin necrosis, characteristic of penile calciphylaxis. The patient has perished of multiorgan failure secondary to severe septic shock.

The CALCIPHYX study: a randomized, double-blind, placebo-controlled, Phase 3 clinical trial of SNF472 for the treatment of calciphylaxis

Background

Calcific uraemic arteriolopathy (CUA; calciphylaxis) is a rare disease seen predominantly in patients receiving dialysis. Calciphylaxis is characterized by poorly healing or non-healing wounds, and is associated with mortality, substantial morbidity related to infection and typically severe pain. In an open-label Phase 2 clinical trial, SNF472, a selective inhibitor of vascular calcification, was well-tolerated and associated with improvement in wound healing, reduction of wound-related pain and improvement in wound-related quality of life (QoL). Those results informed the design of the CALCIPHYX trial, an ongoing, randomized, placebo-controlled, Phase 3 trial of SNF472 for treatment of calciphylaxis.

Methods

In CALCIPHYX, 66 patients receiving haemodialysis who have an ulcerated calciphylaxis lesion will be randomized 1:1 to double-blind SNF472 (7 mg/kg intravenously) or placebo three times weekly for 12 weeks (Part 1), then receive open-label SNF472 for 12 weeks (Part 2). All patients will receive stable background care, which may include pain medications and sodium thiosulphate, in accordance with the clinical practices of each site. A statistically significant difference between the SNF472 and placebo groups for improvement of either primary endpoint at Week 12 will demonstrate efficacy of SNF472: change in Bates-Jensen Wound Assessment Tool-CUA (a quantitative wound assessment tool for evaluating calciphylaxis lesions) or change in pain visual analogue scale score. Additional endpoints will address wound-related QoL, qualitative changes in wounds, wound size, analgesic use and safety.

Conclusions

This randomized, placebo-controlled Phase 3 clinical trial will examine the efficacy and safety of SNF472 in patients who have ulcerated calciphylaxis lesions. Patient recruitment is ongoing.

Calciphylaxis in uraemic and nonuraemic settings: clinical risk factors and histopathological findings

BACKGROUND

Calciphylaxis is a life-threatening cutaneous ulcerative/necrotic disease characterized by vascular calcification/occlusion. It occurs most commonly in end-stage kidney disease (ESKD), known as uraemic calciphylaxis (UC) but can also occur in patients with chronic kidney disease (CKD) and normal kidney function (nonuraemic calciphylaxis; NUC). There are few large series of NUC in the literature.

AIM

To compare the clinicopathological features of UC and NUC.

METHODS

We retrospectively compared the clinicopathological features of 35 patients with NUC during the period 2010-2020 with those of 53 patients with UC (control group). Cases were classified as NUC in the absence of all of the following: ESKD, significant CKD (defined as serum creatinine > 3 mg/dL or creatinine clearance < 15 mL/min) and acute kidney injury requiring kidney replacement therapy or kidney transplantation.

RESULTS

NUC represented 40% of the total cases, and there was a higher number of women (P < 0.01) and a higher median body mass index (P = 0.06) compared with the control UC group. Elevated parathyroid hormone was present in 44% of patients with NUC. Most of the tested patients were positive for lupus anticoagulants (56%). NUC biopsies showed a higher rate of extravascular calcium deposits (73% vs. 47%, P = 0.03). Dermal reactive vascular proliferation was the most common dermal change (32%).

CONCLUSIONS

NUC is more common than previously reported and shows a higher predilection for obese postmenopausal women. Undiagnosed hyperparathyroidism shows a possible association with NUC. Lupus anticoagulants were positive in most patients. NUC biopsies are more likely than UC biopsies to display extravascular calcium deposition.

Development of the BWAT-CUA Scale to Assess Wounds in Patients with Calciphylaxis

Calcific uremic arteriolopathy (CUA; calciphylaxis) is a severe form of vascular calcification with no approved therapies. A standardized wound assessment tool is needed to evaluate changes in calciphylaxis wounds over time. A prospective, single-arm study of 14 patients with calciphylaxis reported improvement for the primary endpoint of wound healing using the 13-item Bates-Jensen Wound Assessment Tool (BWAT), although that tool was developed for assessment of pressure ulcers. This report describes development of BWAT-CUA, an 8-item modification of BWAT focusing on prototypical features of calciphylaxis lesions. The BWAT-CUA has a range of 8 (best) to 40 (worst) and was used ad hoc to analyze BWAT data collected in the prospective study. Using BWAT-CUA, relative improvement in calciphylaxis wounds was 30% overall (from 21.2 to 14.9; p = 0.0016) and 34% in the subset of 12 patients with ulceration at baseline (from 23.3 to 15.3; p = 0.0002). BWAT-CUA is a primary endpoint in an ongoing randomized, placebo-controlled phase 3 study of SNF472 recruiting patients with end-stage kidney disease and at least one ulcerated calciphylaxis lesion. BWAT-CUA, a newly developed tool for assessment of calciphylaxis wound severity and improvements over time, may be used in clinical research and in clinical practice.