Shiga toxin-producing Escherichia coli infection as a precipitating factor for atypical hemolytic-uremic syndrome.

BACKGROUND: Hemolytic uremic syndrome (HUS) is a thrombotic microangiopathy characterized by intravascular hemolysis. It can be classified as either typical, primarily caused by Shiga toxin-producing Escherichia coli (STEC) infection, or as atypical HUS (aHUS), which results from uncontrolled complement activation. METHODS: We report the case of a 9-year-old boy with aHUS due to compound heterozygous complement factor H-related genes (CFHR) 1/3 and CFHR1-CFHR4 deletions, leading to the development of anti-complement factor H (CFH) autoantibodies. The patient presented nephrological and neurological thrombotic microangiopathy with STEC positivity. Additionally, we provide an extensive literature review of aHUS cases initially classified as typical. RESULTS: A total of 11 patients were included, 73% of whom were pediatric. Kidney replacement therapy was required in 73% of patients. The recurrence rate was 55%. All cases were found positive for pathological variants of the complement system genes. The most commonly implicated gene was CFH, while the CFHR genes were involved in 36% of cases, although none exhibited anti-CFH autoantibodies. Anti-complement therapy was administered in 54% of cases, and none of the patients who received it early progressed to kidney failure. CONCLUSIONS: STEC infection does not exclude aHUS diagnosis, and early use of anti-complement therapy might be reasonable in life-threatening conditions. Genetic testing can be helpful in patients with atypical presentations and can confirm the necessity of prolonged anti-complement therapy.

Approach to the child and adolescent with Adrenal Insufficiency.

The management of adrenal insufficiency is challenging, and the overall goals of treatment are to prevent life-threatening adrenal crises, to optimize linear growth, to control androgen levels without overdosing in subjects with congenital adrenal hyperplasia (CAH) and to improve quality of life in affected individuals. Standard glucocorticoid formulations fail to replicate the circadian rhythm of cortisol and control the adrenal androgen production driven by adrenocorticotropic hormone. In order to personalize and tailor glucocorticoid therapy and to improve patient outcomes, new pharmacological strategies have been developed that best mimic physiological cortisol secretion. Novel therapeutic approaches in the management of adrenal insufficiency include new ways to deliver circadian cortisol replacement as well as various adjunctive therapies to reduce androgen production and/or androgen action/effects. Preclinical studies are exploring the role of restorative cell-based therapies, and a first recombinant adeno-associated virus-based gene therapy is also being developed in humans with CAH. In this article, we present three illustrative cases of adrenal insufficiency with different underlying etiologies and times of presentation. Diagnostic and management processes are discussed with emphasis on treatment and outcomes. We have also provided the most up-to-date evidence for the tailored management of children and adolescents with adrenal insufficiency.

Clinical characterization, long-term follow-up, and response to treatment of patients with syndrome of undifferentiated recurrent fever (SURF).

OBJECTIVES: To describe a homogeneous group of patients with undifferentiated recurrent fevers followed-up in a tertiary referral center for systemic autoinflammatory diseases (SAIDs). METHODS: Patients with undifferentiated recurrent fevers seen at our Center from 2008 to 2021 and followed-up for at least one year were included in a retrospective study. Monogenic recurrent fevers, patients carrying variants of unknown origin and PFAPA (Periodic Fever, Aphthous Stomatitis, Pharyngitis, Adenitis) syndrome were excluded. RESULTS: Fifty patients (34 male, 16 female) were included in the study. The median age at onset was 3 years, and the median follow-up was 3.3 years. At baseline, arthralgia (70%) and abdominal pain (65%) were the most frequent manifestations. NSAIDs or steroids on demand had a variable and transient effect. Tonsillectomy was ineffective in the 10 patients (20%) that underwent surgery. Forty-eight patients (96%) were treated with colchicine. A complete response (absence of fever) was achieved in 31 patients (64.6%). Nine patients (18%) showed a partial response, with a median reduction of fever episodes per year of 72%. Nine patients (16.7%) were considered resistant to colchicine. The presence of generalized lymphadenopathy and, to a lesser extent, exudative tonsillitis was associated with a lack of response to colchicine. CONCLUSIONS: We describe the largest series of patients with syndrome of undifferentiated recurrent fever (SURF) reported in the literature so far. SURF should be considered as a distinct clinical entity in the context of multifactorial autoinflammatory diseases.