Dual rare genetic diseases in five pediatric patients: insights from next-generation diagnostic methods

BACKGROUND

Clinicians traditionally aim to identify a singular explanation for the clinical presentation of a patient; however, in some cases, the diagnosis may remain elusive or fail to comprehensively explain the clinical findings. In recent years, advancements in next-generation sequencing, including whole-exome sequencing, have led to the incidental identification of dual diagnoses in patients. Herein we present the cases of five pediatric patients diagnosed with dual rare genetic diseases. Their natural history and diagnostic process were explored, and lessons learned from utilizing next-generation diagnostic technologies have been reported.

RESULTS

Five pediatric cases (3 boys, 2 girls) with dual diagnoses were reported. The age at diagnosis was from 3 months to 10 years. The main clinical presentations were psychomotor retardation and increased muscular tension, some accompanied with liver dysfunction, abnormal appearance, precocious puberty, dorsiflexion restriction and varus of both feet, etc. After whole-exome sequencing, nine diseases were confirmed in these patients: Angelman syndrome and Krabbe disease in case 1, Citrin deficiency and Kabuki syndrome in case 2, Homocysteinemia type 2 and Copy number variant in case 3, Isolated methylmalonic acidemia and Niemann-Pick disease type B in case 4, Isolated methylmalonic acidemia and 21-hydroxylase deficiency in case 5. Fifteen gene mutations and 2 CNVs were identified. Four novel mutations were observed, including c.15292de1A in KMT2D, c.159_164inv and c.1427G > A in SLC25A13, and c.591 C > G in MTHFR.

CONCLUSIONS

Our findings underscore the importance of clinicians being vigilant about the significance of historical and physical examination. Comprehensive clinical experience is crucial for identifying atypical clinical features, particularly in cases involving dual rare genetic diseases.

Pregnancy and neonatal outcomes in 25 pregnant women diagnosed with new-onset acute myeloid leukemia during pregnancy

PURPOSE

The aim was to analyze the pregnancy and neonatal outcomes of pregnant women with new- onset acute myeloid leukemia (AML) diagnosed during pregnancy.

METHODS

In this retrospective study 25 pregnant women who were diagnosed with new-onset AML during pregnancy from January 2010 to January 2021 were enrolled.

RESULTS

A total of 4, 13 and 8 pregnant women with new-onset AML were diagnosed during the first, second, and third trimesters, respectively. Twelve of the 25 pregnant women underwent therapeutic abortion and 13 gave birth (9 preterm and 4 full-term newborns). The gestational age at initial clinical manifestations (13.4 ± 3.7 vs. 27.7 ± 5.6 weeks, P < 0.01) and diagnosis (16.9 ± 4.4 vs. 29.7 ± 5.5 weeks, P < 0.01) was lower in the pregnant women who underwent therapeutic abortion than in those who gave birth. Eighty-four percent (21/25) of the pregnant women with new-onset AML during pregnancy survived and were in remission and all the newborns were born alive. Three of the 13 newborns were exposed to chemotherapy, but no congenital malformations were observed. Eight newborns were admitted to the neonatal intensive care unit (NICU), and all recovered. The complete blood counts and biochemical examinations of the 8 newborns were normal.

CONCLUSIONS

New-onset AML during an earlier stage of pregnancy may increase the risk of poor pregnancy outcomes. The neonatal outcomes of pregnant women with new-onset AML during pregnancy are good with proper treatment.

Long-term follow-up of haploidentical haematopoietic stem cell transplantation in paediatric patients with high-risk acute myeloid leukaemia: Report from a single centre

Data from 200 children with high-risk acute myeloid leukaemia who underwent their first haploidentical haematopoietic stem cell transplantation (haplo-HSCT) between 2015 and 2021 at our institution were analysed. The 4-year overall survival (OS), event-free survival (EFS) and cumulative incidence of relapse (CIR) were 71.9%, 62.3% and 32.4% respectively. The 100-day cumulative incidences of grade II-IV and III-IV acute graft-versus-host disease (aGVHD) were 41.1% and 9.5% respectively. The 4-year cumulative incidence of chronic GVHD (cGVHD) was 56.1%, and that of moderate-to-severe cGVHD was 27.3%. Minimal residual disease (MRD)-positive (MRD+) status pre-HSCT was significantly associated with lower survival and a higher risk of relapse. The 4-year OS, EFS and CIR differed significantly between patients with MRD+ pre-HSCT (n = 97; 63.4%, 51.4% and 41.0% respectively) and those with MRD-negative (MRD-) pre-HSCT (n = 103; 80.5%, 73.3% and 23.8% respectively). Multivariate analysis also revealed that acute megakaryoblastic leukaemia without Down syndrome (non-DS-AMKL) was associated with extremely poor outcomes (hazard ratios and 95% CIs for OS, EFS and CIR: 3.110 (1.430-6.763), 3.145 (1.628-6.074) and 3.250 (1.529-6.910) respectively; p-values were 0.004, 0.001 and 0.002 respectively). Thus, haplo-HSCT can be a therapy option for these patients, and MRD status pre-HSCT significantly affects the outcomes. As patients with non-DS-AMKL have extremely poor outcomes, even with haplo-HSCT, a combination of novel therapies is urgently needed.

[Research progress on neurodevelopmental outcomes of small for gestational age infants]

The incidence of perinatal disease and perinatal mortality in small for gestational age infants increased significantly. This group of people is prone to a variety of long-term metabolic diseases and cardiovascular diseases, and is also prone to growth retardation and neurodevelopmental delay, which will seriously affect the long-term quality of life of children. The article studies the neurodevelopmental outcomes of small-for-gestational-age infants. By reviewing and sorting out previous literature, the neurodevelopmental disorders of small-for-gestational-age infants are analyzed according to five aspects: intellectual development, motor development, language development, sensory development, and mental illness. The classification and summary were carried out, and the influencing factors of neurodevelopmental disorders of SGA were also evaluated, so as to provide reference for promoting the improvement of neurodevelopmental outcomes of small-for-gestational-age infants.