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acute hepatitis a virus ( hav ) infection is common in the developing countries among children , but hydrops of gallbladder due to hepatitis a infection is an uncommon presentation .
a five - year - old boy was admitted in namazi hospital , shiraz , iran due to jaundice and severe abdominal pain for 10 days . physical examination revealed a mass in the right upper quadrant with severe tenderness .
liver function tests were abnormal while other laboratory data such as blood urea nitrogen , serum creatinine , sodium , and potassium were within the normal range .
abdominal ultrasonography showed that the gallbladder was very much distended and its fundus was near the iliac crest .
after five days , without any specific treatment , his symptoms improved and he was discharged with good condition .
acute acalculous gallbladder disease is a rare complication of hav infection which should be suspected in any child with right upper quadrant abdominal pain , tenderness , and mass which can lead to surgical emergency in rare conditions .
the distinction between these two conditions may be difficult . these diseases may present with a spectrum of symptoms ranging from transient gallbladder distention with spontaneous resolution to acute acalculous cholecystitis ( aac ) with necrosis of the gallbladder wall ( 1 ) .
acute hydrops is defined by marked gallbladder distention in the absence of calculi , bacterial infection , or congenital gallbladder anomaly .
the absence of a significant inflammatory component and its typically benign prognosis are the features that distinguish hydrops from acalculous cholecystitis ( 1 ) .
one of the conditions related to gallbladder hydrops is viral hepatitis and gallbladder hydrops due to viral hepatitis a is rarely reported in children ( 2 ) .
here is the presentation of infection in a five - year - old boy with hydrops of gallbladder due to hepatitis a virus ( hav ) , which is rarely reported in the pediatric age group .
a five - year - old boy was admitted in namazi hospital , shiraz , iran with severe abdominal pain , jaundice and low grade fever .
he had abdominal pain and vomiting from 20 days before admission ; his jaundice worsened and developed from 10 days ago . at the time of admission he was very sick with fever and yellowish discoloration of skin and sclera .
he was very irritable due to abdominal pain . in the physical examination he had normal growth parameters and
his vital signs were as follows : temperature : 38c , pulse rate : 100/min , respiratory rate : 30/min and blood pressure : 100/60 mmhg . in the abdominal examination
, a large mass was palpated in the right upper quadrant ( ruq ) with severe tenderness .  
initial laboratory investigations showed elevated liver enzymes : ast : 516 u / l , alt : 722 u / l , alkaline phosphatase : 1930 u / l , total bilirubin : 5.3 mg / dl , direct bilirubin : 3.9 mg / dl , total protein : 7.7 g / dl , albumin : 3.8 g / dl , wbc : 8000/mm , hb : 11.9 g / dl , platelet : 426000/mm , cpr : 6 mg / dl , esr : 40 mm / h .
coagulation studies revealed pt : 13 sec , ptt : 34 sec and inr : 1 .
serum amylase , blood sugar and serum sodium , potassium , bun and creatinine were within normal range .
venous blood gas analysis revealed : ph : 7.5 , hco3 : 30 , and pco2 : 37.9 .
serology of viral hepatitis was positive for hav igm , and other viral markers were negative .
abdominal ultrasonography showed normal size and echogenicity of the liver , with significantly distended gallbladder ( span 130  50 mm ) with the fundus of gallbladder near iliac crest .
the hydrops of gallbladder was confirmed by ultrasonography ( figure 1 ) . due to fever and toxic condition
after the third day of admission , his fever and blood culture became negative and antibiotics were stopped .
after five days , general condition and abdominal pain of and jaundice improved and he was discharged with close follow up .
abdominal ultrasonography showed normal size and echogenicity of the liver , with significantly distended gallbladder ( span 130  50 mm ) ; fundus of gallbladder was near iliac crest .
hepatitis a viral infection is a wide spread infection throughout the world . in the developing countries , hepatitis
92% to 100% of the 18-year - old people have serologic evidence of past infection ( 1 ) .
infants and toddlers are more likely to be asymptomatic ( anicteric hepatitis ) , whereas the majority of adults will develop clinically evident hepatitis ( 1 ) .
one of every 12 young children develops jaundice , and children are more likely than adults ( 60% vs. 20% ) to have diarrhea , often leading to the mistaken diagnosis of infectious gastroenteritis ( 1 ) .
gallbladder hydrops due to hepatitis a viral infection is uncommon and is exceptionally described in the literature ( 2 - 4 ) .  
abdominal pain , vomiting , and ruq mass in abdominal examination are the typical presentations of gallbladder hydrops .
kawasaki syndrome ( 5 ) , mesenteric adenitis with pressure over cystic duct ( 5 ) , streptococcal and staphylococcal infections with the associated toxin production ( 6 ) , viral hepatitis , henoch - schoenlein purpura ( 7 ) and hypokalemia ( 8) had reported association with hydrops of gallbladder .
other etiologies include tumors , polyps or malignancy of the gallbladder , spontaneously resolved acute cholecystitis , congenital narrowing of the cystic duct , parasites such as ascaris ( occasionally ) , prolonged parenteral nutrition , typhoid , leptospirosis , and appropriate response to ceftriaxone therapy ( 1 ) .
although the etiology is unclear , invasion of the gallbladder and bile duct epithelial by hepatitis a viral infection and cell - mediated immunologic response are proposed in the pathogenesis of cholecystitis resulted from hav infection ( 9 ) .  
low grade fever , colicky abdominal pain , vomiting , right sub costal tenderness , and a palpable tender mass in ruq are common ( 1 ) .
a mild , direct hyperbilirubinemia may also be present . if the infection left untreated , it can rapidly progress to gallbladder gangrene and perforation leading to peritonitis , sepsis , and shock . in uncomplicated acute cholecystitis , liver function tests are normal or there is only slightly liver enzyme elevation .
mild cholestatic abnormalities ( increased bilirubin up to 4 mg / dl and elevated alkaline phosphatase ) are common , probably indicating the mechanical obstruction of the cystic duct resulting from intrinsic inflammation of the biliary tract ( 10 ) .
the diagnosis of hydrops is generally made by abdominal ultrasonography demonstrating a markedly distended , echo - free gallbladder with normal wall thickness and a normal - caliber biliary tree .
serial ultrasonographic examination is useful to monitor the patient and detect the resolution ( 10 ) .  
most cases are self - limited and size of the gallbladder may spontaneously become normal with treatment of the underlying disease within approximately two weeks ( 1 ) . in conclusion , in the case of hepatitis a viral infection with severe abdominal pain and
specially ruq abdominal mass , hydrops of gallbladder should be kept in mind as a possible complication and abdominal ultrasonography should be done accordingly .
introduction : acute hepatitis a virus ( hav ) infection is common in the developing countries among children , but hydrops of gallbladder due to hepatitis a infection is an uncommon presentation.case presentation : a five - year - old boy was admitted in namazi hospital , shiraz , iran due to jaundice and severe abdominal pain for 10 days . 
 physical examination revealed a mass in the right upper quadrant with severe tenderness . 
 liver function tests were abnormal while other laboratory data such as blood urea nitrogen , serum creatinine , sodium , and potassium were within the normal range . 
 blood and urine cultures were negative . 
 abdominal ultrasonography showed that the gallbladder was very much distended and its fundus was near the iliac crest . 
 hydrops of the gallbladder was diagnosed . 
 hav igm titer was high . 
 after five days , without any specific treatment , his symptoms improved and he was discharged with good condition.conclusions:acute acalculous gallbladder disease is a rare complication of hav infection which should be suspected in any child with right upper quadrant abdominal pain , tenderness , and mass which can lead to surgical emergency in rare conditions .