Liver abscesses, particularly pyogenic and amoebic types, pose a significant healthcare challenge, especially in developing countries. Accurate differentiation and effective treatment of these abscess types are crucial in emergency medical settings. This study aims to analyze the incidence, clinical characteristics, and treatment outcomes of pyogenic and amoebic liver abscesses in a trauma and emergency department setting.

Conducted at the Indira Gandhi Institute of Medical Sciences (IGIMS), Patna, this one-year observational study involved 100 patients diagnosed with liver abscesses. The study employed a comprehensive approach, examining incidence rates, demographic trends, clinical presentations, treatment modalities, and outcomes, including recurrence rates.

The study observed a higher incidence of pyogenic liver abscesses, accounting for 60% of cases (n=60), compared to amoebic liver abscesses, which constituted 40% (n=40). In terms of demographics, pyogenic liver abscesses were more prevalent among older males, with the average age being 48 years, and 70% (n=42) of the patients were male. In contrast, amoebic liver abscess patients had an average age of 42 years, with 60% (n=24) being male. Key clinical findings revealed that pyogenic liver abscess cases (n=60) had higher white blood cell counts and elevated liver enzyme levels than those with amoebic liver abscesses (n=40). The treatment outcomes indicated high success rates for both types of liver abscesses. Pyogenic liver abscesses had a success rate of 90% (n=54), while amoebic liver abscesses showed a slightly higher success rate at 95% (n=38). However, there was a notable difference in recurrence rates: pyogenic liver abscesses had a recurrence rate of 8.3% (n=5), whereas amoebic liver abscesses had a lower recurrence rate of 2.5% (n=1). The logistic regression analysis conducted to identify potential predictors of treatment success did not reveal any statistically significant factors across both types of liver abscesses.

The study highlights a higher incidence of pyogenic liver abscesses in an urban Indian healthcare setting and the complexity of predicting treatment outcomes based on demographic and clinical factors. The findings emphasize the need for nuanced clinical approaches and vigilant post-treatment monitoring, especially for pyogenic liver abscesses. They also underscore the importance of further research to explore additional variables influencing liver abscess treatment outcomes.

Entamoeba histolytica (E. histolytica) is a facultative protozoan parasite implicated in amoebic liver abscesses (ALA), the most common extraintestinal manifestation of this infection. E. histolytica is endemic to sub-tropical and tropical countries and has been a major public health concern in northern Sri Lanka (SLK) for the last three decades. This has been attributed to a multitude of factors such as poor sanitation, hygiene, male sex, middle age, overcrowding, unsanitary practices in the production of indigenous alcoholic beverages, and alcohol consumption. Additionally, while rates of E. histolytica have declined substantially throughout the rest of the island, largely due to better infrastructure, it remains pervasive in the northern peninsula, which is generally less developed. Infection arises primarily from fecal-oral transmission through the consumption of contaminated drinking water containing cysts. Upon ingestion, cysts multiply into trophozoites and colonize the host colonic mucosa using lectin and cysteine proteases as virulence factors, leading to host invasion. Symptoms occur along a spectrum, from asymptomatology, to pyrexia, abdominal cramping, and amoebic dysentery. Colonization of the colon results in the formation of distinct flask-shaped ulcers along the epithelium, and eventual penetration of the lamina propria via the production of matrix metalloproteinases. ALA then develops through trophozoite migration via the mesenteric hepatic portal circulation, where microabscesses coalesce to form a single, large right-lobe abscess, commonly on the posterior aspect. The progression of infection to invasive disease is contingent on the unique interplay between host and pathogen factors, such as the strength of host-immunity to overcome infection and inherent pathogenicity of the Entamoeba species. As a preventable illness, E. histolytica complications such as ALA impose a significant burden on the healthcare system. This mini-review highlights epidemiological trends, risk factors, diagnostic modalities, treatment approaches, and opportunities for prevention of E. histolytica-induced ALA, to help address this endemic problem on the island of SLK.

A 26-year-old man who was previously well presented to the emergency in septic shock. He had a preceding history of fever, right upper abdominal pain and jaundice. On examination, there was tenderness over the right hypochondrium and epigastrium, without features of generalised peritonitis. His blood tests were suggestive of sepsis with deranged liver function tests. CT scan of the abdomen showed multiples abscesses in various segments of the liver and a thrombus in the inferior venacava, without any other intraabdominal focus of infection. The abscess was aspirated under sonographic guidance, and the cultures grew Streptococcus constellatus species of S. milleri group (SMG). He received crystalline penicillin, based on culture sensitivity and underwent drainage of the abscess. There was a clinical improvement and he was subsequently discharged in a stable condition. On 3 months follow-up, there was a complete resolution of the liver abscess and normalisation of the liver function tests.

Since 1985, amoebic liver abscess (ALA) has been a public health problem in northern Sri Lanka. Clinicians arrive at a diagnosis based on clinical and ultrasonographic findings, which cannot differentiate pyogenic liver abscess (PLA) from ALA. As the treatment and outcome of the ALA and PLA differs, determining the etiological agent is crucial.

All clinically diagnosed ALA patients admitted to the Teaching Hospital (TH) in Jaffna during the study period were included and the clinical features, haematological parameters, and ultrasound scanning findings were obtained. Aspirated pus, blood, and faecal samples from patients were also collected. Pus and faeces were examined microscopically for amoebae. Pus was cultured in Robinson's medium for amoebae, and MacConkey and blood agar for bacterial growth. ELISA kits were used for immunodiagnosis of Entamoeba histolytica infection. DNA was extracted from selected pus samples and amplified using nested PCR and the purified product was sequenced.

From July 2012 to July 2015, 346 of 367 clinically diagnosed ALA patients admitted to Jaffna Teaching Hospital were enrolled in this study. Almost all patients (98.6%) were males with a history of heavy alcohol consumption (100%). The main clinical features were fever (100%), right hypochodric pain (100%), tender hepatomegaly (90%) and intercostal tenderness (60%). Most patients had leukocytosis (86.7%), elevated ESR (85.8%) and elevated alkaline phosphatase (72.3%). Most of the abscesses were in the right lobe (85.3%) and solitary (76.3%) in nature. Among the 221 (63.87%) drained abscesses, 93.2% were chocolate brown in colour with the mean volume of 41.22 ± 1.16 ml. Only four pus samples (2%) were positive for amoeba by culture and the rest of the pus and faecal samples were negative microscopically and by culture. Furthermore, all pus samples were negative for bacterial growth. Antibody against E. histolytica (99.7%) and the E. histolytica antigen were detected in the pus samples (100%). Moreover, PCR and sequencing confirmed these results.

To our knowledge, this is the first report from Sri Lanka that provides immunological and molecular confirmation that Entamoeba histolytica is a common cause of liver abscesses in the region.