[MIM 262 500]

(Laron type dwarfism, primary insensitivity to growth hormone, pituitary dwarfism type 2)

Very rare: 1 to 10 /million. More common in the Mediterranean or Middle East populations. Autosomal recessive transmission of a deletion or mutation of the GHR (growth hormone receptor) gene (5p13-p12). This results in an inability to produce insulin-like growth factor 1 (IGF-1).

Some cases of similar phenotype associated with immune deficiency and caused by a STAT5B mutation [MIM 245 590: Laron-like syndrome or short stature with STAT5B deficiency] have been described. The immunodeficiency is characterized by moderate lymphopenia, leading to recurrent infections of the skin and the respiratory system. Severe chronic lung disease, chronic diarrhea, juvenile idiopathic arthritis, generalized eczema, lung infections, alveolar proteinosis and respiratory failure have already been observed.

Clinical picture of a harmonious dwarfism (as in case of growth hormone deficiency) that does not respond to treatment with exogenous growth hormone and is accompanied by high blood levels of growth hormone: adult size varies from - 3 to -12 standard deviations of the mean of the population. The size at birth is normal.

Beside the short stature:

-         facial dysmorphism: high and prominent forehead, shallow orbits, hypoplastic nose, mandibular hypoplasia, small chin, high-pitched voice

-         risk of hypoglycemia (perinatal and early childhood)

-         motor development delay 

-         truncal obesity

-         delayed puberty 

-         osteopenia: risk of fractures

-         hypercholesterolemia

-         occasionally narrow spinal canal.

An experimental treatment with subcutaneous injections of mecasermine (human recombinant IGF1) is under investigation.

Anesthetic implications: 

short stature; narrow pharynx, obstructive sleep apnea, risk of hypoglycemia, osteoporosis. Risk of instability of the atlas-axis joint and separation of the dens of the axis: careful intubation ! Titration of the dose of local anesthetic in case of neuraxial block. In case of immunodeficiency: antibioprophylaxis, perioperative respiratory kinesitherapy.

References : 

-         Bhatia K, Cockerham R. 
Anaesthetic management of a parturient with Laron syndrome. 
Int J Obstetr Anesth 2011; 20: 344-6. 

-        Eklund SE, Levin DN.
Lung isolation for whole lung lavage in a pediatric patient with atypical airway anatomy due to short stature : a case report.
A&A Practice 2019 ; 13 : 253-6

Updated: October 2019