Microgallbladder

Microgallbladder is a common abdominal manifestation of cystic fibrosis. It defines a gallbladder that has a length less than 2-3 cm and a width less than 0.5-1.5 cm on sonographic evaluation .

Epidemiology

The incidence of microgallbladder varies considerably in the literature, however most studies cite an incidence of 25-35% in patients with cystic fibrosis . In patients without cystic fibrosis, it is a very rare entity, but may have an association with idiopathic neonatal hepatitis and biliary atresia .

Clinical presentation

The presence of a microgallbladder is asymptomatic . Symptoms may become apparent if there is concurrent cholelithiasis or cholecystitis .

Pathology

The pathogenesis of microgallbladder in patients with cystic fibrosis is not well understood. The most popular hypothesis considers microgallbladder to be a result of chronic inflammation secondary to gallstone disease leading to gross atrophy of the gallbladder.

Radiographic features

Microgallbladder can be evaluated on ultrasound or cross-sectional imaging, although may be difficult to visualize routinely on ultrasound . On these modalities, microgalbladder is defined by :

  • length: <2-3 cm
  • width: <0.5-1.5 cm

There may or may not be associated gallstone disease (e.g. cholelithiasis, gallbladder sludge, etc.) present during radiographic evaluation .

Treatment and prognosis

Generally, no treatment is necessary .