Early cardiomyopathy without severe metabolic dysregulation in a patient with cblB-type methylmalonic acidemia.

BACKGROUND: Cardiomyopathy is a known complication of organic acidemias but generally thought to be secondary to poor metabolic control. METHODS: Our patient was found through biochemical testing and Sanger sequencing to harbor an Icelandic founder mutation: NM_052845.4(MMAB):c.571C > T(p.Arg191Trp), leading to an early presentation (4 h after birth) of cblB-type methylmalonic acidemia (MMA). Biochemical testing of this patient suggested B-12-responsiveness and thus the patient was treated with cyanocobalamin throughout life. Informed parental consent was obtained for this report. RESULTS: Our patient had three metabolic decompensations in her life (at birth, at 1 month, and at 5 months). The first decompensation was probably linked to stress of delivery, second to rhinovirus infection, and third by co-infection of norovirus and enterovirus. At 3 months, the patient was noted to be tachypneic, although this was attributed to her underlying metabolic acidosis. At 5 months and 10 days, the patient was admitted with minor flu-like symptoms but developed severe diarrhea in hospital and upon rehydration had cardiac decompensation and was found to have undiagnosed dilated cardiomyopathy. Although, patient was treated aggressively with dextrose, hemodialysis, levocarnitine, and vasoactive agents, there was limited response to medications to treat cardiac failure, and eventually the patient passed away before turning 6 months old. CONCLUSIONS: Other than these three mild decompensations, patient had very good metabolic control, thus demonstrating that even without frequent metabolic decompensation, cardiomyopathy can be an observed phenotype in cblB-type MMA even very early in life, suggesting that this phenotype may be independent of metabolic control.

Survey of 23 Nordic university hospitals showed that 77% lacked written procedures for measuring and interpreting blood pressure in infants.

AIM: This study determined the use of standardised procedures for infant noninvasive blood pressure (NIBP) measurements in the Nordic countries and aimed to identify factors included in the standardisation and interpretation of NIBP measurements in infants. METHODS: A cross-sectional electronic questionnaire survey was sent to 84 physicians in all 23 university hospitals in Sweden, Norway, Denmark, Finland and Iceland and was completed from February to March 2017. The survey contained respondent characteristics, the presence and description of standardised procedures for NIBP measurements, daily practice of NIBP measurements and methodological considerations and interpretation of NIBP measurements in a healthy six-month-old child. RESULTS: We received responses from 55 of 84 physicians working in all 23 Nordic university hospitals, in paediatric cardiology (n = 22), general paediatrics (n = 16), paediatric nephrology (n = 14) and other fields (n = 3). Less than a quarter (23%) said their hospital issued specific NIBP procedures relating to infants and they referred to 19 different sources of information. The factors that were most commonly assessed for interpretation were age (100%), arousal state (78%) and cuff size (76%). CONCLUSION: Most of the university hospital units treating children lacked age-specific written procedures for measuring and interpreting infant NIBP, and there is a strong need for common Nordic guidelines.