Clinical characteristics and risk factors associated with mortality in calcific uremic arteriolopathy

Clinical characteristics and treatment modalities in uremic and non uremic calciphylaxis - a dermatological single-center experience

Calciphylaxis (CP) is a serious, potentially life-threatening disease that presents with medial calcification of small-sized vessels and painful ischemic ulcerations. Although calciphylaxis is frequently seen in patients with end-stage kidney disease on dialysis (calcific uremic arteriolopathy, CUA), there are reported cases of nonuremic calciphylaxis (NUC), which often remain undiagnosed. We conducted a retrospective chart review at our dermatological hospital and evaluated data concerning the epidemiology, comorbidities, medication, laboratory abnormalities, and therapeutic approaches of 60 patients diagnosed with calciphylaxis between 01/2012 and 12/2022. We identified 21 patients diagnosed with NUC and 39 with kidney disease. The predilection sites of skin lesions were the lower legs in 88% (n = 53), followed by the thigh and gluteal regions in 7% (n = 4). Significant differences were identified in comorbidities, such as atrial fibrillation (p < 0.001) and hyperparathyroidism (p < 0.01) accounting for CUA patients. Medication with vitamin K antagonists (p < 0.001), phosphate binders (p < 0.001), and loop diuretics (p < 0.01) was found to be associated with the onset of calciphylaxis. Hyperphosphatemia (p < 0.001), increased parathyroid hormone (p < 0.01) and triglyceride levels (p < 0.01), hypoalbuminemia (p < 0.01) and decreased hemoglobin values (p < 0.001) in the CUA cohort were significantly different from those in the NUC group. All patients with CUA received systemic medication. In contrast, only 38% (n = 8) of patients with NUC received systemic treatment. Striking discrepancies in the treatment of both cohorts were detected. In particular, NUC remains a disease pattern that is still poorly understood and differs from CUA in several important parameters.

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.

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.

Rapidly Progressive and Catastrophic Calciphylaxis After Mechanical Valve Replacement: An Anticoagulation Dilemma

Warfarin is the only approved anticoagulant after mechanical valve replacement, but it is a well described risk factor for calciphylaxis among patients with end-stage kidney disease. Our patient with end-stage kidney disease rapidly developed calciphylaxis after dual mechanical valve replacement in association with warfarin initiation, posing significant challenges in clinical management and a fatal outcome. (Level of Difficulty: Intermediate.).

Therapeutic effect of intravenous sodium thiosulfate for uremic pruritus in hemodialysis patients

Objectives

This study aimed to compare the efficacy of intravenous sodium thiosulfate (IV STS) with that of loratadine in the treatment of uremic pruritus in hemodialysis (HD) patients.

Methods

This retrospective study included 44 HD patients with pruritus aged over 18 years between June 2018 and January 2020 at the Aerospace Center Hospital of China. Twenty-four HD patients received 3.2 g IV STS treatment three times per week at the end of each HD session for 8 weeks. Twenty HD patients received loratadine (10 mg/day) for 8 weeks. Pruritus intensity was measured using a visual analog scale (VAS) and the detailed pruritus score (DPS) at three time points. The safety of STS was evaluated according to adverse event symptoms and biological variable changes.

Results

There was no significant difference between the STS and loratadine groups in age, sex, characteristics of pruritus, or other clinical variables before treatment. After 8 weeks of treatment, the VAS score (7.07 ± 2.56 and 2.67 ± 2.01) and DPS (30.72 ± 4.81 and 8.04 ± 2.86) decreased significantly in the STS group (p < 0.05). The mean decrease in VAS score (6.89 ± 1.98 and 6.34 ± 2.35) and DPS (28.90 ± 3.24 and 26.92 ± 2.41) in the loratadine group was not statistically significant (p > 0.05). There were no morbidities or mortalities associated with the use of either drug. All biological variables remained stable after therapy.

Conclusions

STS can improve uremic pruritus in HD patients. However, literature on the subject remains lacking. Close monitoring for adverse effects is advised.

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

BACKGROUND AND AIMS

Calciphylaxis is a rare condition associated with very high mortality in patients with end-stage kidney disease. Data from country-based registries have been an invaluable resource for a better understanding of the natural history and management for this condition. This study aimed to investigate the current management strategies and outcomes of patients enrolled in the United Kingdom Calciphylaxis study (UKCS).

METHODS

The study was conducted on 89 patients registered in the UKCS since 2012. The initial analysis included a description of the baseline characteristics, management strategies and outcomes on follow-up until May 2020. Further analysis included a comparison of the mortality outcome of the UKCS patients who were receiving haemodialysis with a propensity score matched cohort of haemodialysis patients from the Chronic Renal Insufficiency Standards Implementation Study- Haemodialysis (CRISIS-HD).

RESULTS

Median age of the cohort was 59 years, with a predominance of females (61%) and Caucasian (95%) ethnicity. About 54% of the patients were diabetic and 70% were receiving haemodialysis at study entry. The skin lesions were mostly distributed in the lower extremities (48%). Sodium thiosulphate and calcimimetic were the most widely used management strategies. The mortality rate was 72 deaths per hundred patient-years (50 deaths observed in 69.5 patient years). Complete wound healing was noted in 17% and bacteraemia was reported in 26% of patients. In a comparative analysis of the matched haemodialysis patients, the presence of calciphylaxis in 62 patients showed a strong association with all-cause mortality (HR 6.96; p < 0.001), with annual mortality 67% versus 10.2% in haemodialysis patients without calciphylaxis.

CONCLUSIONS

This UK wide study strengthens the evidence that calciphylaxis is a strong and independent risk factor associated with all-cause mortality; no significant benefit was shown with any individual treatment modality. Until further evidence becomes available, a multifaceted approach would be the appropriate treatment strategy in the management of this extremely serious condition.

Pathophysiology of atrial fibrillation and chronic kidney disease

Atrial fibrillation (AF) and chronic kidney disease (CKD) are closely related conditions with shared risk factors. The growing prevalence of both AF and CKD indicates that more patients will suffer from concurrent conditions. There are various complex interlinking mechanisms with important implications for the management of these patients. Furthermore, there is uncertainty regarding the use of oral anticoagulation (OAC) in AF and CKD that is reflected by a lack of consensus between international guidelines. Therefore, the importance of understanding the implications of co-existing AF and CKD should not be underestimated. In this review, we discuss the pathophysiology and association between AF and CKD, including the underlying mechanisms, risk of thrombo-embolic and bleeding complications, influence on stroke management, and evidence surrounding the use of OAC for stroke prevention.

Stroke Prophylaxis in Patients with Atrial Fibrillation and End-Stage Renal Disease

Atrial fibrillation (AF) is an important comorbidity in patients with end-stage renal disease (ESRD) undergoing dialysis that portends increased health care utilization, morbidity, and mortality in this already high-risk population. Patients with ESRD have a particularly high stroke risk, which is further compounded by AF. However, the role of anticoagulation for stroke prophylaxis in ESRD and AF is debated. The ESRD population presents a unique challenge because of the combination of elevated stroke and bleeding risks. Warfarin has been traditionally used in this population, but it is associated with significant risks of minor and major bleeding, particularly intracranial, thus leading many clinicians to forgo anticoagulation altogether. When anticoagulation is prescribed, rates of adherence and persistence are poor, leaving many patients untreated. The direct oral anticoagulants (DOACs) may offer an alternative to warfarin in ESRD patients, but these agents have not been extensively studied in this population and uncertainties regarding comparative effectiveness (versus warfarin, each other, and no treatment) remain. In this review, we discuss the current evidence on the risk and benefits of anticoagulants in this challenging population and comparisons between warfarin and DOACs, and review future directions including options for non-pharmacologic stroke prevention.

Calciphylaxis: Approach to Diagnosis and Management

Calciphylaxis is a rare disorder of poor prognosis that can lead to intense, painful lesions involving the skin and subcutaneous tissue. Although mostly described in dialysis patients, it can affect patients with normal kidney function. The diagnosis of calciphylaxis is complicated by the absence of a gold standard marker of disease such as a clear histopathological finding. Late diagnosis and advanced lesions can significantly shorten life expectancy. Calciphylaxis wounds can have a major influence on the quality of life of patients, usually due to the immense unbearable pain these patients suffer from. The management of calciphylaxis mainly comprises aggressive wound care and symptomatic management. Therapeutic options are few and far between and are limited to off-label uses. Recent understanding of the pathogenesis of lesions has enabled development of novel therapeutic options, some of which are being studied in clinical trials (sodium thiosulfate, vitamin K). Vascular calcification and thrombosis underlie development of these lesions and research has been aimed at studying drugs that counteract such processes. Future research is required to establish clear causal pathways and improve on the treatment options currently available to patients.

The color of skin: black diseases of the skin, nails, and mucosa

Gradations in skin color are a consequence of differing amounts of melanin and their varying distribution. Although many darkly pigmented skin lesions are melanocytic and can be attributed to melanin content, the color of a black lesion can also be due to blood, necrotic tissue, or exogenous pigment. The source, pattern, and distribution of the color in black lesions usually offer important insight into its etiology. This contribution reviews conditions that can take on a black color, discussing the cause of the hue and any additional impact sun exposure may have.

Calciphylaxis mimicking ecthyma gangrenosum

Calciphylaxis is a rare cutaneous disease that may cause fatal complications in patients on long-term dialysis. Early diagnosis and proper management decrease complications. However, it can mimic cutaneous infections, especially ecthyma gangrenosum and cutaneous vasculitis. The authors report on a patient with chronic kidney disease (CKD) on dialysis for 10 years who developed painful skin necrosis on his right thigh. The tissue culture was positive for Enterobacter cloacae, Citrobacter freundii, and Pseudomonas aeruginosa, but the histopathology was compatible with calciphylaxis. This report aims to further the knowledge of physicians in order to help them recognize calciphylaxis in CKD patients with painful necrotic ulcers.

Anticoagulation in Patients With Advanced Chronic Kidney Disease: Walking the Fine Line Between Benefit and Harm

Chronic kidney disease affects more than 3 million Canadians and is highly associated with cardiovascular diseases that require anticoagulation, such as atrial fibrillation and venous thromboembolism. Patients with chronic kidney disease are at a problematic crossroads; they are at high risk of thrombotic conditions requiring anticoagulation and bleeding complications due to anticoagulation. The limited high-quality clinical evidence to guide decision-making in this area further compounds the dilemma. In this review, we discuss the physiology and epidemiology of bleeding and thrombosis in patients with kidney disease. We specifically focus on patients with advanced kidney disease (estimated glomerular filtration rate ≤ 30 mL/min) or who are receiving dialysis and focus on the nephrologist perspective regarding these issues. We summarize the existing evidence for anticoagulation use in the prevention of stroke with atrial fibrillation and provide practical clinical recommendations for considering anticoagulation use in this population. Last, we examine specific scenarios such as the use of a glomerular filtration rate estimating equation and dosing, the use of existing prediction tools for stroke and hemorrhage risk, current patterns of anticoagulation use (including during the dialysis procedure), and vascular calcification with vitamin K antagonist use in patients with chronic kidney disease.

Warfarin in nonvalvular atrial fibrillation-Time for a change?

Warfarin is the most commonly prescribed anticoagulant in hemodialysis (HD) patients with nonvalvular atrial fibrillation (NVAF). Recent trends show that Nephrologists are increasingly prescribing novel oral anticoagulants, despite the fact that no randomized clinical trials have been conducted in dialysis patients. Difficulties maintaining international normalized ratio in the therapeutic range, increased risk of intracranial hemorrhage and concerns regarding warfarin-induced vascular calcification and calciphylaxis may be responsible. Anticoagulation quality is poor in HD patients. A variety of factors contribute to this: increased antibiotic exposure; comorbid illness; decreased adherence and vitamin K deficiency. Attempts to address this with standardized protocols have been uniformly unsuccessful. In nonadherent patients, thrice weekly observed therapy improved quality. Low-dose vitamin K supplementation improves time in the therapeutic range (TTR) in those with normal kidney function and should be studied in HD patients given their high frequency of vitamin K deficiency. Vascular and valvular calcification associated with warfarin could result from reduced carboxylation of matrix Gla protein (MGP), a well-known inhibitor of vascular calcification. Multiple observational studies also link calciphylaxis to warfarin; warfarin-induced hypercoagulability and decreased carboxylation of MGP could explain this. A large observational study, two meta-analyses, and a systematic review in HD patients with NVAF showed reduced bleeding with apixaban compared to warfarin with similar efficacy in reducing stroke and systemic embolism. Given these results, apixaban is a reasonable alternative to warfarin for anticoagulation of HD patients with NVAF, especially in those with low TTR, until data from randomized clinical trials become available.

Calciphylaxis: Successful Management of a Rare Complication of Chronic Kidney Disease in Two Patients

Calciphylaxis, or calcification uremic arteriolopathy, is a rare disease thought to occur due to arteriolar calcifications of the dermis and is responsible for ischemia with cutaneous necrosis and painful panniculitis. Its mechanism remains poorly understood which makes its management challenging and difficult to standardize. We report our management of two patients diagnosed with calciphylaxis. In one patient, calciphylaxis was mentioned upon admission given the context of preexisting secondary hyperparathyroidism and the existence of multiple risk factors. In both patients, the diagnosis was confirmed histologically. Our two observations highlight the difficulty of the diagnosis and the complexity of the therapeutic management that has been personalized according to patient characteristics and clinical evolution. Several therapeutic means can be implemented once the diagnosis is made; nevertheless, its prognosis remains pejorative despite the therapeutic advances. Broad debridement, good phosphocalcic balance control, and the correction of the risk factors top the list of any therapeutic strategy. One of the major challenges of the therapy is normalizing the calcium-phosphate balance. Thus, Cinacalcet and sodium thiosulfate appear to be promising treatments.

Treatment of Calciphylaxis in CKD: A Systematic Review and Meta-analysis

BACKGROUND

Calciphylaxis is a life-threatening complication of chronic kidney disease (CKD). To inform clinical practice, we performed a systematic review of case reports, case series, and cohort studies to synthesize the available treatment modalities and outcomes of calciphylaxis in patients with CKD.

METHODS

Electronic databases were searched for studies that examined the uses of sodium thiosulfate, surgical parathyroidectomy, calcimimetics, hyperbaric oxygen therapy, and bisphosphonates for calciphylaxis in patients with CKD, including end-stage renal disease. For cohort studies, the results were synthesized quantitatively by performing random-effects model meta-analyses.

RESULTS

A total of 147 articles met the inclusion criteria and were included in the systematic review. There were 90 case reports (90 patients), 20 case series (423 patients), and 37 cohort studies (343 patients). In the pooled cohorts, case series, and case reports, 50.3% of patients received sodium thiosulfate, 28.7% underwent surgical parathyroidectomy, 25.3% received cinacalcet, 15.3% underwent hyperbaric oxygen therapy, and 5.9% received bisphosphonates. For the subset of cohort studies, by meta-analysis, the pooled risk ratio for mortality was not significantly different among patients who received sodium thiosulfate (pooled risk ratio [RR] 0.89; 95% confidence interval [CI] 0.71-1.12), cinacalcet (pooled RR 1.04; 95% CI 0.75-1.42), hyperbaric oxygen therapy (pooled RR 0.89; 95% CI 0.71-1.12), and bisphosphonates (pooled RR 0.77; 95% CI 0.44-1.32), and those who underwent surgical parathyroidectomy (pooled RR 0.88; 95% CI 0.69-1.13).

CONCLUSION

This systematic review found no significant clinical benefit of the 5 most frequently used treatment modalities for calciphylaxis in patients with CKD. Randomized controlled trials are needed to test the efficacy of these therapies.