Currently, there is no evidence in the literature to support the routine supplementation of all parenterally fed premature infants with l-carnitine. In our study, we found that about 8.56% of extremely preterm neonates are diagnosed with carnitine deficiency secondary to malnutrition, either due to reduced stores at birth or related to total parenteral nutrition (TPN). Our two step approach of performing newborn screening (NBS) again at 32 weeks gestational age (GA) equivalent helps to diagnose 81.4% more preterm babies with carnitine deficiency—who would otherwise be missed—and supplement them with l-carnitine for optimal growth. We performed a retrospective cohort study to diagnose carnitine deficiency related to malnutrition in two groups: those presenting at birth and those presenting later in life. We found that there was a statistically significant difference in the median GA and birth weight (BW) between the two groups, but there was no difference in the free carnitine levels.

Background: Newborn screening is an essential public health strategy that aims to detect a range of conditions, including inborn errors of metabolism, in neonates shortly after birth. The timely identification is crucial due to the asymptomatic nature of many conditions at birth, but which can lead to significant health complications if left untreated. Through this study, we aimed to investigate the incidence of IEMs screened by the Qatar National Newborn Screening Program. Methods: We retrospectively analyzed a total of 351,223 newborns screened from 2010 to 2023. The incidence for the studied IEMs was calculated and correlated with demographics, consanguinity, and family history. In addition, the diagnostic yield of different tests utilized was assessed. Results: Our study revealed a total of 318 positive cases with IEMs, and a significantly high incidence of 1:1105 for IEMs in Qatar. Classical Homocystinuria was the most frequently detected condition, with a cumulative incidence of 1:6754 live births, linked to the founder variant p. Arg336Cys in the CBS gene. Aminoacidopathies were the most prevalent category, followed by fatty acid oxidation disorders, organic acidurias, biotinidase deficiency, and urea cycle disorders. Genetic testing showed a high diagnostic yield of 90%. Of the 60 cases that underwent targeted variant testing, 98% were confirmed, while 90% of the 59 cases tested by single gene testing were confirmed. Conclusions: Our study provides the incidence rates of IEMs in Qatar and novel insights that could facilitate setting up/developing IEM incidence-reducing strategies and improving outcomes for affected newborns and their families.

Malonic aciduria is a rare autosomal recessive organic acid disorder. With the widespread use of tandem mass spectrometry for analysis of the amino acid/acylcarnitine profile on dried blood spots for newborn screening (NBS), this condition can be readily diagnosed and can be included in the organic acid screen in NBS programs. In Qatar, we report the first case of an asymptomatic baby screened and diagnosed with malonic aciduria through NBS. This patient has a genetic variant of malonyl-CoA decarboxylase that has not been previously reported in the literature. This condition should be differentiated from a similar disorder, combined malonic and methylmalonic aciduria. The clinical phenotype of malonic aciduria is variable and the pathophysiology is not fully understood. There is no established guidance or recommendations regarding the appropriate treatment regimen, dietary therapy or regular follow-up of these patients. Most available evidence for treatment is based on a single study or case report.

We present an interesting case of porphria cutanea tarda with hereditary haemochromatosis and non-classical congenital adrenal hyperplasia in a postmenopausal woman. This unusual combination of conditions does not appear to be reported in the literature. The exact mechanism causing porphyria in this patient is not clear. We consider the possibility that in addition to iron accumulation and excess alcohol, altered steroid milieu may have been a possible trigger for the development of bullous lesions in this patient.