PCSK1 deficiency

Proprotein convertase subtilisin/kexin type 1 (PCSK1) deficiency is caused by biallelic variants in the PCSK1 gene.12

PCSK1 deficiency is inherited in an autosomal recessive manner

Inheritance

PCSK1 deficiency is inherited in an autosomal recessive manner.12,39

Individuals can have biallelic or heterozygous variants of PCSK1.39 Variants may be identified through genetic testing, and results can be discussed with a geneticist.

Common features

Primary signs and symptoms include:7,39,40

GI Symptoms, including postnatal diarrhea within the first weeks of life

GI symptoms, including postnatal diarrhea within the first weeks of life

Metabolic acidosis, Polydipsia/polyuria
  • Metabolic acidosis
  • Polydipsia/polyuria
Hyperinsulinemia
  • Some form of diabetes
  • Hyperinsulinemia
  • Hypoglycemia
Early onset obesity

Early-onset, severe obesity

Additional signs and symptoms may include:

  • Hyperphagia
  • Hypothyroidism
  • Failure to thrive in infancy
  • Hypocortisolism
PCSK1 deficiency may be diagnosed with genetic testing

Diagnosis

Diagnosis of PCSK1 deficiency may be suspected by clinical presentation of the disease and confirmed via genetic testing.

Learn more

Treatment

Find out about a treatment option for PCSK1 deficiency.

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  • References

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