Acute Kidney Injury and Hair-Straightening Products: A Case Series.

RATIONALE & OBJECTIVE: Keratin-based hair-straightening treatment is a popular hair-styling method. The majority of keratin-based hair-straightening products in Israel contain glycolic acid derivatives, which are considered safe when used topically. Systemic absorption of these products is possible, and anecdotal reports have described kidney toxicity associated with their use. We report a series of cases of severe acute kidney injury (AKI) following use of hair-straightening treatment in Israel during the past several years. STUDY DESIGN: Case series. SETTING & PARTICIPANTS: We retrospectively identified 26 patients from 14 medical centers in Israel who experienced severe AKI and reported prior treatment with hair-straightening products in 2019-2022. FINDINGS: The 26 patients described had a median age of 28.5 (range, 14-58) years and experienced severe AKI following a hair-straightening procedure. The most common symptoms at presentation were nausea, vomiting, and abdominal pain. Scalp rash was noted in 10 (38%) patients. Two patients experienced a recurrent episode of AKI following a repeat hair-straightening treatment. Seven patients underwent kidney biopsies, which demonstrated intratubular calcium oxalate deposition in 6 and microcalcification in tubular cells in 1. In all biopsies, signs of acute tubular injury were present, and an interstitial infiltrate was noted in 4 cases. Three patients required temporary dialysis. LIMITATIONS: Retrospective uncontrolled study, small number of kidney biopsies. CONCLUSIONS: This series describes cases of AKI with prior exposure to hair-straightening treatments. Acute oxalate nephropathy was the dominant finding on kidney biopsies, which may be related to absorption of glycolic acid derivatives and their metabolism to oxalate. This case series suggests a potential underrecognized cause of AKI in the young healthy population. Further studies are needed to confirm this association and to assess the extent of this phenomenon as well as its pathogenesis.

Effect of early nephrology referral on the mortality of dialysis patients in Israel.

BACKGROUND: Late nephrology referral, before initiation of dialysis treatment, is associated with adverse outcome. OBJECTIVES: To investigate the implications of late nephrology referral on mortality among dialysis patients in Israel. METHODS: We retrospectively analyzed 200 incident dialysis patients. Patients were defined as late referrals if they started dialysis less than 3 months after their first nephrology consultation. Survival rates and risk factors for mortality were analyzed RESULTS: The early referral (ER) group comprised 118 patients (59%) and the late referral (LR) group 82 patients (41%). The mortality rate was 44.5% (53 patients) in the ER and 68% (n = 56) in the LR group. The 4 year survival rate was 41.1% in the ER and 18.7% in the LR group (P < 0.0001). The mortality rate increased with late nephrology referral (HR 1.873, 95% CI 1.133-3.094), with age (HR 1.043 for each year, 95% CI 1.018-1.068), with diabetes (HR 2.399, CI 1.369-4.202), and with serum albumin level (HR 0.359 for an increase of each 1 g/dl, 95% CI 0.242-0.533). The median survival time was higher for the ER group in women, in patients younger than 70, and in diabetic patients. A trend for longer survival time was found in non-diabetic patients. Survival time was not increased in early referred patients older than 70 and in male patients. CONCLUSIONS: Late nephrology referral is associated with an overall higher mortality rate in dialysis patients. The survival advantage of early referral may have a different significance in specific subgroups. The timing of nephrology referral should be considered as a modifiable risk factor for mortality in patients with end-stage renal disease.