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Primary Pulmonary Hypertension Associated with Asymptomatic Methylmalonic Aciduria in a Child
Fatma Zohra Chioukh1, Kamel Monastiri1
1Department of Intensive Care and Neonatal Medicine, Faculty of Medicine, University of Monastir, Tunisia.
Abstract:
Methylmalonic acidemia or aciduria (MMA) is an inborn error of metabolism that results in the accumulation of methylmalonic acid in blood with an increased excretion in urine. MMA usually presents in early infancy and its effects vary from mild to life-threatening. The clinical symptoms mainly include vomiting, dehydration, hypotonia, developmental delay, and failure to thrive. An association between pulmonary arterial hypertension (PAH) and MMA has been rarely reported. In the present work, the authors report a 16-month boy, who was admitted to the Pediatric Department for cyanosis and fever. He had a family history of primary pulmonary hypertension in a sister. The echocardiography showed a mild pericardial effusion and PAH. The metabolic screening led to the diagnosis of MMA. The condition of the baby worsened rapidly- and he died a few days later. Physicians should be aware about this atypical presentation of the disease, which can be fatal if not diagnosed and managed promptly.
Insights
Methylmalonic acidemia (MMA) is a rare metabolic disorder. This case highlights a rare association between MMA and pulmonary arterial hypertension (PAH) in an infant, emphasizing the need for prompt diagnosis.
Area of Science:
- Metabolic Disorders
- Pediatric Cardiology
- Genetics
Background:
- Methylmalonic acidemia (MMA) is an inborn error of metabolism.
- Clinical manifestations of MMA typically include vomiting, dehydration, hypotonia, developmental delay, and failure to thrive.
- An association between MMA and pulmonary arterial hypertension (PAH) is rarely reported.
Observation:
- A 16-month-old boy presented with cyanosis and fever, with a family history of primary pulmonary hypertension.
- Echocardiography revealed mild pericardial effusion and pulmonary arterial hypertension (PAH).
- Metabolic screening confirmed the diagnosis of Methylmalonic acidemia (MMA).
Findings:
- The patient's condition rapidly deteriorated, leading to death within days.
- This case highlights a rare, atypical presentation of Methylmalonic acidemia (MMA).
Implications:
- Physicians must consider MMA in infants presenting with unexplained pulmonary arterial hypertension (PAH).
- Prompt diagnosis and management of MMA are critical to prevent potentially fatal outcomes.
- Increased awareness of the MMA-PAH association is necessary for timely intervention in affected infants.
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