A case report of fatal harlequin ichthyosis: Insights into infectious and respiratory complications

Retinoid Therapy in a Case of Harlequin Ichthyosis with a Short Literature Review

Harlequin ichthyosis (HI) is a genetically inherited epidermal disorder due to the mutation of the ABCA12 gene, which is responsible for lipid transportation, and presents with large keratinised scales characterised by deep erythematous fissures, with ectropion and eclabium. A moderate number of cases and a high mortality rate have been recorded. In this case report, a pregnant lady gave birth to a 33-week-old premature foetus with characteristic symptoms of HI. After admitting him to the NICU, a multidisciplinary treatment approach was conducted with paediatric dermatologists, ophthalmologists, urologists, and dieticians. The prognosis is positive, with desquamation of the hyperkeratotic plate revealing an erythematous and shiny skin. A short literature review on HI characteristics, diagnostic aids, and management has also been added.

Case Report: Novel rare mutation c.6353C > G in the ABCA12 gene causing harlequin ichthyosis identified by whole exome sequencing

BACKGROUND

Harlequin ichthyosis (HI) is a severe rare genetic disease that mainly affects the skin. Neonates with this disease are born with thick skin and large diamond-shaped plates covering most of their bodies. Affected neonates lose the ability to control dehydration and regulate temperature and are more susceptible to infections. They also face respiratory failure and feeding problems. These clinical symptoms are factors associated with high mortality rates of neonates with HI. Until now, there are still no effective treatments for HI patients and most patients die in the newborn period. Mutation in the ABCA12 gene, which encodes an adenosine triphosphate-binding cassette (ABC) transporter, has been demonstrated as the major cause of HI.

CASE PRESENTATION

In this study, we report the case who is one infant that was born prematurely at 32 gestational weeks with the whole body covered with thick plate-like scales of skin. The infant was severely infected with mild edema, multiple cracked skins full of the body, yellow discharge, and necrosis of fingers and toes. The infant was suspected to be affected by HI. Whole exome sequencing (WES) was performed as a tool for detecting the novel mutation in one prematurely born Vietnam infant with HI phenotype. And after that, the mutation was confirmed by the Sanger sequencing method in the patient and the members of his family. In this case, one novel mutation c.6353C > G (p.S2118X, Hom) in the ABCA12 gene, was detected in the patient. The mutation has not been reported in any HI patients previously. This mutation was also found in a heterozygous state in the members of the patient's family, including his parents, an older brother, and an older sister who are no symptoms.

CONCLUSIONS

In this study, we identified a novel mutation in a Vietnamese patient with HI by whole exome sequencing. The results for the patient and the members of his family will be helpful in understanding the etiology of the disease, diagnosing carriers, assisting in genetic counseling, and emphasizing the need for DNA-based prenatal screening for families with a history of the disease.

Harlequin ichthyosis newborn: A case report

Harlequin ichthyosis is a rare and severe genetic skin disorder that occurs within the developing foetus. Harlequin ichthyosis is the most severe and devastating form of autosomal recessive congenital ichthyoses. It is caused by mutations in the lipid transporter adenosine triphosphate binding cassette A 12. Here, we reported a case of harlequin ichthyosis with no family history. No abnormalities were detected in prenatal sonography. A 24-year-old pregnant woman with premature rupture of membrane and labour pain was referred to a hospital in Shoushtar city, Iran. The mother delivered a male baby with harlequin ichthyosis. The infant baby died on the 5th day. Harlequin ichthyosis is associated with adenosine triphosphate binding cassette A 12 gene mutation; therefore, genetic screening and counselling for susceptible parents should be taken into account. Prenatal diagnosis of harlequin ichthyosis principally via sonographic techniques is important in managing the disorder.

Prenatal diagnosis of a rare variant of harlequin ichthyosis with literature review

Background

Harlequin ichthyosis (HI) is a rare and severe genetic skin disorder that occurs within the developing foetus. Due to the extremely poor prognosis, prenatal diagnosis becomes very important, especially for foetuses with no family history. There are few reports on prenatal diagnosis in PubMed.

Case presentation

We report two cases of HI with no family history who were diagnosed by prenatal ultrasound. We searched for reports on the prenatal ultrasonic diagnosis of HI over nearly two decades and summarized the sonographic features of HI, the reasons for missed diagnoses and matters needing attention. A total of 10 articles of congenital harlequin ichthyosis diagnosed by prenatal ultrasound in PubMed were retrieved. There have been even fewer reports of late-trimester disease with no family history. Combining the two cases we reported with the literature review, we summarize the ultrasonic image characteristics of HI.

Conclusion

HI can be easily detected by 2D ultrasound combined with 3D, but attention should be paid to a systematic examination in the third trimester of pregnancy according to the clinical characteristics of the disease.

A harlequin ichthyosis pig model with a novel ABCA12 mutation can be rescued by acitretin treatment

Harlequin ichthyosis (HI) is a severe genetic skin disorder and caused by mutation in the ATP-binding cassette A12 (ABCA12) gene. The retinoid administration has dramatically improved long-term survival of HI, but improvements are still needed. However, the ABCA12 null mice failed to respond to retinoid treatment, which impedes the development of novel cure strategies for HI. Here we generated an ethylnitrosourea mutagenic HI pig model (named Z9), which carries a novel deep intronic mutation IVS49-727 A>G in the ABCA12 gene, resulting in abnormal mRNA splicing and truncated protein production. Z9 pigs exhibit significant clinical symptom as human patients with HI. Most importantly, systemic retinoid treatment significantly prolonged the life span of the mutant pigs via improving epidermal maturation, decreasing epidermal apoptosis, and triggering the expression of ABCA6. Taken together, this pig model perfectly resembles the clinical symptom and molecular pathology of patients with HI and will be useful for understanding mechanistic insight and developing therapeutic strategies.

Two successive cases of fetal harlequin ichthyosis: A case report

Harlequin ichthyosis (HI) is a genetic skin disorder characterized by thickening and splitting of the skin. In fetuses presenting with the disorder, the mortality rate is markedly high. A number of fetal HI cases have been documented. The present study reports a case of a pregnant woman who underwent two successive pregnancies at the ages of 35 and 36, respectively, with both fetuses presenting with HI. The first fetus was delivered alive though succumbed shortly after birth, while the second fetus was stillborn and birthed by induced labor. The fetuses exhibited typical features of fetal HI, including thick, platelike scaling and fissuring, which act as a nidus for infection. The present study is the first to report two cases of fetal HI from successive pregnancies in the same woman. Improved understanding of the genetic basis of HI indicates that genetic screening for candidate gene mutations related to HI, particularly mutations in the adenosine triphosphate binding-cassette transporter ABCA12, may prove beneficial in prenatal diagnosis. Establishing methods for early diagnosis of fetal HI may reduce the physical and mental distress to parents and relatives.