salmonellosis is a well - known cause of morbidity and mortality in patients , particularly in endemic areas .
it is also a well - known cause of pyogenic liver abscess [ 1 , 2 ] .
it is frequently encountered in patients with pre - existing liver pathology such as amoebic abscess or echinococcus cyst .
we present a case of salmonellosis complicated by pyogenic liver abscess in a previously known simple liver cyst .
this signifies the importance of the fact that simple cysts can become a focus of abscess formation .
a 74-year - old gentleman presented to the accident and emergency department following a 3-month stay in india .
four weeks into his return , he started developing daily episodes of fever and night sweats .
whilst in india , he was asymptomatic although he did not take any malaria prophylaxis or salmonella vaccine during his travel .  
he was also known to have a simple cyst measuring 5  cm in diameter in the right lobe of the liver , incidentally found on routine abdominal ultrasonography ( usg ) .
he did not take any regular medication , and was otherwise in good health . on examination
, he had a temperature of 38.2c ,   pulse 90 beats per minute regular , and blood pressure of 116/60  mmhg .
his initial blood biochemical examination showed normal liver and kidney functions but a raised c - reactive protein ( crp ) of 129  mg / dl .
his haematological parameters showed a raised white cell count of 12  000/cumm with predominant neutrophilia .
repeated blood and urine cultures were obtained and abdominal usg requested to find any abdominal collection as a source of sepsis .
the delayed start of his symptoms vis a vis his travel history made viral aetiology , namely , dengue fever unlikely .   
his blood culture grew salmonella paratyphi a. serologies for amoeba and hydatid disease were negative .
abdominal usg showed a collection in the right liver lobe , the same site as the simple cyst noted on the previous scans .
the liver abscess was drained under ultrasound guidance using a pigtail catheter and the aspirate cultures also grew salmonella paratyphi a. the patient received systemic antibiotic , ceftriaxone 2  gm intravenously once daily for 10 days based on the sensitivity report and made an uneventful recovery . on followup , he remains asymptomatic .
we present a case of liver abscess caused by salmonella paratyphi a , in a previously known simple cyst of the liver .
the disease severity varies from mild self - limited gastroenteritis to septicaemia and abscess formation , the later being a major cause of morbidity and mortality .  
salmonella infection can involve any part of the abdomen , but most commonly involves the hepatobiliary system and spleen .
certain conditions such as malignancies , sickle cell disease , liver cirrhosis , and gastric achlorhydria predispose to intra - abdominal salmonella sepsis [ 79 ] .   salmonellosis is often diagnosed on blood cultures and stool cultures .
pyogenic liver abscess ( pla ) is a rare presentation and most frequently caused by bacteroides , enterococcus , e. coli , klebsiella , streptococcus , staphylococcus , and salmonella spp .
it is diagnosed by ultrasound guided sampling of collection followed by culture and repeated blood cultures .
it is occasionally difficult to diagnose pyogenic liver disease as in up to 50% of the pla , blood cultures are negative .  
it is important to consider an alternative diagnosis of amoebic liver disease in a traveller returning from tropics as was our patient .
absence of antibodies after one week of symptoms is almost exclusive of amoebic liver disease and stool examination for detection of cysts is recommended in case patient is a carrier for the infection .
tumours of the hepatobiliary region can occasionally mimic liver abscess whilst an underlying malignancy on liver abscess is associated with poor prognosis [ 1214 ] .
there has also been a case report of salmonella in polycystic liver disease . in one case report of polycystic liver disease ,
one of the cysts became infected with salmonella javiana that was successfully treated with percutaneous drainage and systemic antibiotic followed by installation of intracystic tetracycline as a sclerosant thus preventing a laparotomy .
similarly pla caused by salmonella enteritidis has been reported in a returned traveller with hiv infection .
many strategies have been proposed for treatment of pyogenic liver abscesses depending on their initial size on ct or ultrasound abdomen .
some studies suggest that small abscesses ( less than 3  cm ) should be treated with intravenous antibiotics alone .
large uniloculated ( more than 3  cm ) abscesses should be treated with intravenous antibiotics and percutaneous drainage in the form of ultrasound guided needle aspiration or percutaneous catheter drainage .
surgical or laparoscopic drainage has been recommended for large ( more than 3  cm ) multiloculated collections .
other studies suggest treatment with antibiotics alone on abscesses less than 5  cm , and percutaneous drainage or surgery for sizes more than or equal to 5  cm .  
our case illustrates the value of percutaneous ultrasound guided drainage either by needle aspiration or by catheter drainage to reduce the time for resolution of sepsis and prevention of mortality .
it also illustrates the fact that simple liver cysts can be a focus of pyogenic liver abscess and can be treated effectively with percutaneous catheter insertion and intravenous antibiotic therapy directed by microbiological sensitivities .
 salmonellosis , endemic in various part of the world , is considered a differential diagnosis in a tropical traveller . 
 although it usually presents as gastroenteritis , its various clinical syndromes may vary from mild gastroenteritis to severe septicaemia including abscess formation , the later two being the most common cause of morbidity and mortality . here 
 we present a patient who returned to the uk after an overseas trip and was diagnosed with a pyogenic liver abscess with salmonella paratyphi at a site of a pre - existing simple liver cyst . 
1. Introduction
2. Case Presentation
3. Discussion