Le traitement de la calciphylaxie par cinacalcet : une alternative médicale à la parathyroïdectomie

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.

The use of cinacalcet for the treatment of calciphylaxis in patients with chronic kidney disease: A comprehensive review

Calciphylaxis is a rare but life-threatening condition, most commonly affecting patients with stage 4 or 5 chronic kidney disease. No universally accepted therapy exists so far. In an attempt to avoid surgical intervention with parathyroidectomy, which is of questionable efficacy and carries several risks, a number of noninvasive treatments have been trialled with variable success. These treatments are aimed at modifying risk factors for calciphylaxis, in particular hypercalcaemia, hyperphosphataemia and hyperparathyroidism. The aim of this review was to summarise the available evidence to determine the potential role of cinacalcet in the treatment of calciphylaxis in patients with chronic kidney disease. Demographic, clinical and laboratory data were retrospectively collected from the available English and non-English literature. Overall, there was a very high response rate (partial or complete) of calciphylaxis lesions to both cinacalcet monotherapy and cinacalcet as part of a combination therapy (83.4% and 82.8%, respectively). When examining complete response to treatment specifically, combination therapy with cinacalcet proved more efficacious than monotherapy (62.1% versus 41.7%). There was also an associated rapid reduction of intact parathyroid hormone over a period of 2-33 months in both groups. While there are limitations as to how our data can be interpreted due to the heterogeneity of the methods and follow-up of the included case reports and case series, prompt and consistent therapy including cinacalcet may help improve the disease outcome. Additional research needs to be performed in this area, to further define the optimal use of cinacalcet for the treatment of calciphylaxis.

Calciphylaxis Presenting with Various Symptoms: A Case Report

Calciphylaxis causes ischemia in multiple organs and skin ulcers owing to progressive calcification in small and medial arteries. It has a poor prognosis and often occurs in patients with hyperparathyroidism associated with end-stage renal failure and those undergoing hemodialysis. Here, we present a case of calciphylaxis associated with a wide range of symptoms, including lower thigh skin ulcers, a rectovaginal fistula, and femoral neck fracture. The patient underwent multiple treatments. However, she eventually died of cardiac failure.

Multimodal treatment of calcific uraemic arteriolopathy (calciphylaxis): a case series

Background

This is an incident series of five dialysis patients with late-diagnosed calcific uraemic arteriolophathy (CUA), severe uncontrolled hyperparathyroidism and infected skin ulcerations.

Methods

A multimodal intervention was based on wound care, antibiotics, surgical debridement, sodium thiosulphate and cinacalcet and associated with regression of skin disease in four cases after varying treatment time periods ranging from 4 to 33 months.

Results

Multimodal treatment including sodium thiosulphate and cinacalcet was associated with very favourable local outcomes and survival. This series further confirms that the diagnosis of CUA is rarely made at the nodular, non-ulcerative phase of the disease.

Conclusions

This series contributes to the build-up of case series reporting on the treatment of CUA, and will hopefully serve as a basis of well-conceived comparative effectiveness studies investigating the value of the combined interventions applied so far in this severe condition.

Sistemic calciphylaxis and thrombotic microangiopathy in a kidney transplant patient: two mixing fatal syndromes?

Abnormalities in calcium and phosphorus metabolism are common and metabolic bone diseases develop often in patients with chronic renal failure (CRF). Effective clinical management includes measures to control phosphorus retention and prevent hyperphosphataemia, to maintain serum calcium concentrations within the normal range and to prevent excess parathyroid hormone (PTH) secretion by the judicious use of vitamin D sterols. Certain of these interventions, however, appear to increase the risk of soft tissue and vascular calcification in patients with End Stage Renal Disease (ESRD), so current therapeutic approaches are thus being re-evaluated in an effort to limit these risks. Patients with calciphylaxis have an extremely high mortality rate, diagnosis requires a high degree of clinical suspicion and the role and extent of parathyroidectomy in the management of this condition remain controversial. In some cases renal transplant patients could suffer from a comorbidity in which vascular function is compromised not only by secondary hyperparathyroidism-related calcification but also by other pathological condition as haemolytic uremic syndrome (HUS), leading to a fatal clinical outcome. We postulate that in these cases a secondary hyperparathyroidism not properly diagnosed in an early phase of the renal disease (probably before the kidney transplant) could cause a vascular calcification which, adding to the pre-existing HUS-related vascular compromission, gave rise to catastrophic clinical consequences. In the management of ESRD patients, in particular in the cases of pre-existing angiopathies, could be therefore crucial the early and proper diagnosis of an alteration of calcium-posphorus metabolism and effort of medicine could be oriented in these cases also towards identification of screening methodologies to undoubtedly assess such a diagnosis.

[Cutaneous calciphylaxis]

Calciphylaxis represents a dermatological emergency with a mortality of up to 80%. The disease is characterized by a triad of arteriolar medial calcification, thrombotic cutaneous ischemia and necrotic ulcerations. Recently several mechanisms of vascular calcification have been identified. This may led to preventive measures in the future. Early diagnosis is important to avoid complications such as sepsis. The dermatologist plays an important role in early diagnosis based on the recognition of clinical presentation and histopathology. Patients with end-stage renal disease are most commonly affected by calciphylaxis. The most frequent non-uremic predisposing conditions are primary hyperparathyroidism, malignancies, alcohol-induced liver disease, and autoimmune connective tissue diseases. Medical treatment aims to normalize mineral metabolism to reduce the serum concentration of sodium phosphate and thus to prevent precipitation and calcification. Newer compounds are bisphosphonates, non-sodium/non-aluminium phosphate binders, cinacalcet, paricalcitrol, and sodium thiosulfate. Among the surgical procedures parathyroidectomy did not result in a significant survival benefit. An aggressive surgical debridement of necrotic ulcerations, on the other hand, improved survival. Early diagnosis and a multidisciplinary treatment approach including re-vascularization by the vascular surgeon, repeated surgical debridement and split skin transplantation support wound healing and insure limb conservation.

Calcific uremic arteriolopathy: contemporary pharmacotherapy

Calcific uremic arteriolopathy (CUA) is a poorly understood disease affecting 4% to 5% of the patients with end-stage renal disease. Strategies aimed at prompt identification and diagnosis, such as use of plain radiographs, bone scans, and transcutaneous oxygen saturation tension, may lead to earlier initiation of treatment. Early treatment should focus on preventing progression into overt ulceration, which significantly raises the likelihood of infection, amputation, and death. Several agents, including sodium thiosulfate, bisphosphonates, cinacalcet, and tissue plasminogen activator, have been used in the treatment of CUA with varying effects; however, there has been no consensus on an optimal treatment option. The lack of randomized trials comparing treatment options and a potential bias with respect to publication of case reports hinders the ability to choose the most effective agent in the treatment of CUA. Future insights into the molecular basis of vascular calcification may help determine new therapeutic targets.