Familial hypercholesterolaemia in children and adolescents from 48 countries: a cross-sectional study

Background Approximately 450 000 children are born with familial hypercholesterolaemia worldwide every year, yet only 2·1% of adults with familial hypercholesterolaemia were diagnosed before age 18 years via current diagnostic approaches, which are derived from observations in adults. We aimed to characterise children and adolescents with heterozygous familial hypercholesterolaemia (HeFH) and understand current approaches to the identification and management of familial hypercholesterolaemia to inform future public health strategies. Methods For this cross-sectional study, we assessed children and adolescents younger than 18 years with a clinical or genetic diagnosis of HeFH at the time of entry into the Familial Hypercholesterolaemia Studies Collaboration (FHSC) registry between Oct 1, 2015, and Jan 31, 2021. Data in the registry were collected from 55 regional or national registries in 48 countries. Diagnoses relying on self-reported history of familial hypercholesterolaemia and suspected secondary hypercholesterolaemia were excluded from the registry; people with untreated LDL cholesterol (LDL-C) of at least 13·0 mmol/L were excluded from this study. Data were assessed overall and by WHO region, World Bank country income status, age, diagnostic criteria, and index-case status. The main outcome of this study was to assess current identification and management of children and adolescents with familial hypercholesterolaemia. Findings Of 63 093 individuals in the FHSC registry, 11 848 (18·8%) were children or adolescents younger than 18 years with HeFH and were included in this study; 5756 (50·2%) of 11 476 included individuals were female and 5720 (49·8%) were male. Sex data were missing for 372 (3·1%) of 11 848 individuals. Median age at registry entry was 9·6 years (IQR 5·8–13·2). 10 099 (89·9%) of 11 235 included individuals had a final genetically confirmed diagnosis of familial hypercholesterolaemia and 1136 (10·1%) had a clinical diagnosis. Genetically confirmed diagnosis data or clinical diagnosis data were missing for 613 (5·2%) of 11 848 individuals. Genetic diagnosis was more common in children and adolescents from high-income countries (9427 [92·4%] of 10 202) than in children and adolescents from non-high-income countries (199 [48·0%] of 415). 3414 (31·6%) of 10 804 children or adolescents were index cases. Familial-hypercholesterolaemia-related physical signs, cardiovascular risk factors, and cardiovascular disease were uncommon, but were more common in non-high-income countries. 7557 (72·4%) of 10 428 included children or adolescents were not taking lipid-lowering medication (LLM) and had a median LDL-C of 5·00 mmol/L (IQR 4·05–6·08). Compared with genetic diagnosis, the use of unadapted clinical criteria intended for use in adults and reliant on more extreme phenotypes could result in 50–75% of children and adolescents with familial hypercholesterolaemia not being identified. Interpretation Clinical characteristics observed in adults with familial hypercholesterolaemia are uncommon in children and adolescents with familial hypercholesterolaemia, hence detection in this age group relies on measurement of LDL-C and genetic confirmation. Where genetic testing is unavailable, increased availability and use of LDL-C measurements in the first few years of life could help reduce the current gap between prevalence and detection, enabling increased use of combination LLM to reach recommended LDL-C targets early in life. Funding Pfizer, Amgen, Merck Sharp & Dohme, Sanofi–Aventis, Daiichi Sankyo, and Regeneron

Familial hypercholesterolaemia in children and adolescents from 48 countries: a cross-sectional study

Background: Approximately 450 000 children are born with familial hypercholesterolaemia worldwide every year, yet only 2·1% of adults with familial hypercholesterolaemia were diagnosed before age 18 years via current diagnostic approaches, which are derived from observations in adults. We aimed to characterise children and adolescents with heterozygous familial hypercholesterolaemia (HeFH) and understand current approaches to the identification and management of familial hypercholesterolaemia to inform future public health strategies. Methods: For this cross-sectional study, we assessed children and adolescents younger than 18 years with a clinical or genetic diagnosis of HeFH at the time of entry into the Familial Hypercholesterolaemia Studies Collaboration (FHSC) registry between Oct 1, 2015, and Jan 31, 2021. Data in the registry were collected from 55 regional or national registries in 48 countries. Diagnoses relying on self-reported history of familial hypercholesterolaemia and suspected secondary hypercholesterolaemia were excluded from the registry; people with untreated LDL cholesterol (LDL-C) of at least 13·0 mmol/L were excluded from this study. Data were assessed overall and by WHO region, World Bank country income status, age, diagnostic criteria, and index-case status. The main outcome of this study was to assess current identification and management of children and adolescents with familial hypercholesterolaemia. Findings: Of 63 093 individuals in the FHSC registry, 11 848 (18·8%) were children or adolescents younger than 18 years with HeFH and were included in this study; 5756 (50·2%) of 11 476 included individuals were female and 5720 (49·8%) were male. Sex data were missing for 372 (3·1%) of 11 848 individuals. Median age at registry entry was 9·6 years (IQR 5·8-13·2). 10 099 (89·9%) of 11 235 included individuals had a final genetically confirmed diagnosis of familial hypercholesterolaemia and 1136 (10·1%) had a clinical diagnosis. Genetically confirmed diagnosis data or clinical diagnosis data were missing for 613 (5·2%) of 11 848 individuals. Genetic diagnosis was more common in children and adolescents from high-income countries (9427 [92·4%] of 10 202) than in children and adolescents from non-high-income countries (199 [48·0%] of 415). 3414 (31·6%) of 10 804 children or adolescents were index cases. Familial-hypercholesterolaemia-related physical signs, cardiovascular risk factors, and cardiovascular disease were uncommon, but were more common in non-high-income countries. 7557 (72·4%) of 10 428 included children or adolescents were not taking lipid-lowering medication (LLM) and had a median LDL-C of 5·00 mmol/L (IQR 4·05-6·08). Compared with genetic diagnosis, the use of unadapted clinical criteria intended for use in adults and reliant on more extreme phenotypes could result in 50-75% of children and adolescents with familial hypercholesterolaemia not being identified. Interpretation: Clinical characteristics observed in adults with familial hypercholesterolaemia are uncommon in children and adolescents with familial hypercholesterolaemia, hence detection in this age group relies on measurement of LDL-C and genetic confirmation. Where genetic testing is unavailable, increased availability and use of LDL-C measurements in the first few years of life could help reduce the current gap between prevalence and detection, enabling increased use of combination LLM to reach recommended LDL-C targets early in life

Reactive thrombocytosis in children with upper urinary tract infections

The relationship between reactive thrombocytosis and the level of urinary tract infections was studied in 48 children. Platelets were counted before, during and after treatment. Reactive thrombocytosis was noticed in 74% of children with upper and in 14% with lower urinary tract infections. A significant rise in the platelet count presented in another five children (15%) with upper urinary tract infections. Conclusion: Reactive thrombocytosis was found almost exclusively in the renal parenchymal infections, usually during the recovery phase

Early effect of sodium valproate and carbamazepine monotherapy on homocysteine metabolism in children with epilepsy

Plasma total homocysteine (p-tHcy), serum folate (s-F), serum vitamin B-12 (s-B12) and plasma pyridoxal-5′-phosphate (p-PLP) were measured in epileptic children before and after a 20-week period of sodium valproate (group A, n = 32) and carbamazepine (group B, n = 20) monotherapy. P-tHcy significantly increased in both groups, s-F and s-B12 significantly increased in group A, while s-F and p-PLP significantly decreased in group B. Our study showed an early effect of antiepileptic drug treatment on homocysteine metabolism. © 2006 Elsevier B.V. All rights reserved

A toddler with acute flaccid paralysis due to West Nile virus infection

We report on a 2-year-old boy with acute flaccid paralysis due to West Nile neuroinvasive disease. Serum and cerebrospinal fluid serology as well as nerve conduction studies were consistent with the diagnosis. He received intravenous immunoglobulin and showed gradual improvement and complete recovery of his muscle strength, gait and deep tendon reflexes. Copyright © 2013 by Lippincott Williams & Wilkins

Classic transient erythroblastopenia of childhood with human parvovirus B19 genome detection in the blood and bone marrow

The etiology of transient crythroblastopenia of childhood (TEC) remains unknown, although an association with viral infections has been proposed. The authors describe a 3.5-year-old girl with classic TEC concomitantly with human parvovirus B19 (HPV) infection. The infection was evident by detection of HPV genome in the blood and the bone marrow by polymerase chain reaction. Viral genome was no longer detected when the TEC resolved clinically. The patient was immunocompetent and the anemia has not recurred. To the authors’ knowledge, this is one of the few documented cases of classic TEC attributable to HPV infection

Thyroid function in children with epilepsy treated with sodium valproate monotherapy: A prospective study

OBJECTIVE:: Studies on the effects of sodium valproate (VPA) on thyroid hormone balance in patients with epilepsy are conflicting. The aim of this study was to prospectively evaluate the changes in thyroid profile in children with epilepsy treated with VPA monotherapy. METHODS:: Serum thyroxine, free thyroxine, triiodothyronine, and thyrotropin (TSH) levels were evaluated in 30 children with epilepsy, before and at 6, 12, and 24 months of VPA monotherapy. RESULTS:: All children had normal thyroid function before the initiation of VPA treatment. Serum VPA concentrations remained within the therapeutic range (50-100 mg/L) during the period of study. Thyroxine and free thyroxine levels were significantly decreased, whereas TSH levels were significantly increased at 6, 12, and 24 months of VPA therapy. Triiodothyronine levels were significantly decreased only at 24 months of therapy. Thirteen children (43.3%) at 6 months, 14 children (46.6%) at 12 months, and 15 children (50%) at 24 months of treatment had TSH values greater than 5 mIU/mL. Normal serum TSH levels were restored in all 8 children examined at 3 months after withdrawal of medication. CONCLUSIONS:: Valproate monotherapy may cause significant alteration in thyroid profile in children with epilepsy, occurring early in the course of treatment and persisting as long as VPA is initiated. Therefore, it may be useful to measure serum thyroid hormone concentrations routinely in children with epilepsy taking VPA. Further prospective studies are required to determine the mechanisms and risk factors for development of thyroid disturbance in children treated with VPA monotherapy. © 2009 Lippincott Williams & Wilkins