Outcomes of a conservative approach to management in amoebic liver abscess

Amebic liver abscess: An update

Amebic liver abscess (ALA) is still a common problem in the tropical world, where it affects over three-quarters of patients with liver abscess. It is caused by an anaerobic protozoan Entamoeba hystolytica, which primarily colonises the cecum. It is a non-suppurative infection of the liver consisting primarily of dead hepatocytes and cellular debris. People of the male gender, during their reproductive years, are most prone to ALA, and this appears to be due to a poorly mounted immune response linked to serum testosterone levels. ALA is more common in the right lobe of the liver, is strongly associated with alcohol consumption, and can heal without the need for drainage. While majority of ALA patients have an uncomplicated course, a number of complications have been described, including rupture into abdomino-thoracic structures, biliary fistula, vascular thrombosis, bilio-vascular compression, and secondary bacterial infection. Based on clinico-radiological findings, a classification system for ALA has emerged recently, which can assist clinicians in making treatment decisions. Recent research has revealed the role of venous thrombosis-related ischemia in the severity of ALA. Recent years have seen the development and refinement of newer molecular diagnostic techniques that can greatly aid in overcoming the diagnostic challenge in endemic area where serology-based tests have limited accuracy. Metronidazole has been the drug of choice for ALA patients for many years. However, concerns over the resistance and adverse effects necessitate the creation of new, safe, and potent antiamebic medications. Although the indication of the drainage of uncomplicated ALA has become more clear, high-quality randomised trials are still necessary for robust conclusions. Percutaneous drainage appears to be a viable option for patients with ruptured ALA and diffuse peritonitis, for whom surgery represents a significant risk of mortality. With regard to all of the aforementioned issues, this article intends to present an updated review of ALA.

Preoperative Transcatheter Arterial Embolization for Spontaneous Rupture of Huge Amebic Liver Abscess with Massive Intraperitoneal Hemorrhage

An 18-year-old male developed a huge liver abscess with severe anemia over the course of 2 weeks. Abdominal contrast enhanced computed tomography showed ruptured huge liver abscess in the right liver lobe with signs of active hemorrhage (contrast extravasation). Serology examination confirmed amoeba as the suspected pathogen of cause. Angiography was performed followed by transcatheter arterial embolization to localize and control the hemorrhage. Embolization using a combination of polyvinyl alcohol and gelfoam successfully controlled the active hemorrhage. Exploratory laparotomy was performed to evacuate and debride the huge abscess. Metronidazole was given and showed good results. Huge liver abscess size is a predictor of conservative management failure and requires a gradual step-up intervention. The purpose of this paper is to explain the importance of imaging in detecting liver abscess and active hemorrhage along with the role of interventional radiology in this case.

Role of Pigtail Catheter Drainage Versus Percutaneous Needle Aspiration in the Management of Liver Abscess: A Retrospective Analysis

Introduction

A liver abscess is an important health concern in tropical countries. Effective management of liver abscesses includes appropriate antibiotics and drainage of the abscess cavity. Percutaneous abscess drainage by pigtail catheterization is now gaining popularity. We analyzed the role of pigtail catheter drainage over percutaneous aspiration in the treatment of liver abscesses.

Methods and material

This was a retrospective analytical study conducted in a tertiary care center in western India. Patients of age ≥ 18 years admitted with the diagnosis of liver abscess were included in this study. To find the effectiveness of different treatment modalities, data were analyzed in three groups: Group A (Conservative treatment), Group B (Percutaneous needle aspiration), and Group C (Pigtail catheter drainage).

Results

A total of 64 patients with a liver abscess were analyzed. There was male predominance (93.75%). Mean abscess volume in Group C (307.9 ± 212.8 ml) was significantly higher when compared to Group A (130.8 ± 72.9 ml, p = 0.03) and Group B (177.2 ± 129.5; p = 0.024). The duration of hospital stay and residual abscess volume at the time of discharge did not show a statistically significant difference between treatment groups. Pigtail catheterization of abscesses with volume >150 ml shortened the hospital stay, whereas it prolonged the hospital stay in patients with abscess volume <150 ml.

Conclusion

Percutaneous pigtail catheterization would be an operative decision for the management of liver abscess. We concluded that the use of pigtail catheterization of patients with abscess volume > 150 ml improved the clinical outcome.

Evaluating the efficacy of nitazoxanide in uncomplicated amebic liver abscess

BACKGROUND

Amebic liver abscess is treated successfully with metronidazole or another nitroimidazole drug followed by a luminal amebicide. Metronidazole has long been preferred, but has been associated with several adverse effects including intolerance in certain clinical situations. Mechanisms of metronidazole resistance and mutagenic potential have been described. Effects of the use of drug in pregnant women and infants of lactating women are unknown. Nitazoxanide was proven to be efficacious in treating invasive intestinal amebiasis. Therefore, the present study was undertaken to assess the efficacy and safety of nitazoxanide as compared to metronidazole in patients with uncomplicated amebic liver abscess.

METHODS

Patients with clinical and ultrasonography features suggestive of liver abscess, positive amebic serology, and/or anchovy sauce appearance on aspiration of the pus were included in the study and randomized into two parallel treatment groups. Group M received metronidazole, 2-2.5 g/day intravenous (IV), for inpatients, or 2-2.4 g/day oral, for outpatients in three divided doses for 14 days. Group N received nitazoxanide 500 mg BD per oral for 10 days.

RESULTS

A total of sixty subjects fulfilling the inclusion criteria were randomized equally into two groups, group M and group N. Number of patients achieving symptomatic clinical response (SCR) was similar in the two groups (80% vs. 76.7%, p = 1.00), though time to achieve symptomatic clinical response was significantly lower in metronidazole group as compared to that in nitazoxanide group. Greater proportion of patients achieved early clinical response (ECR) in metronidazole group as compared to nitazoxanide group. Complete resolution of abscess, at 6 months, was noted in 18 (60%) patients in the M group and 22 (73.3%) patients in the N group (p = 0.273). Metronidazole was associated with significantly greater frequency of adverse effects than nitazoxanide.

CONCLUSIONS

This study shows equivalent efficacy of nitazoxanide in uncomplicated amebic liver abscess as compared to metronidazole, with better tolerability and advantage of simultaneous luminal clearance, thus reducing chances of recurrence.

TRIAL REGISTRATION

CTRI/2019/01/017249.

Huge Amoebic Liver Abscess in the Left Lobe Treated by Oral Administration of Metronidazole

A man in his 60s visited a clinic with chief complaints of a fever and general malaise. Suspecting a liver abscess in the left lobe with infiltration into the subcutaneous fat tissue under the rectus abdominis muscle based on computed tomography findings, we performed fine-needle aspiration. An amoebic liver abscess was diagnosed. Remission was achieved by the oral administration of metronidazole alone without placement of a drainage tube. The results obtained in this case suggest that the first line of treatment should be a non-invasive approach with oral administration alone. Invasive intervention should then be considered depending on subsequent progress.

Evidence-based therapeutic dilemma in the management of uncomplicated amebic liver abscess: A systematic review and meta-analysis

BACKGROUND

The role of metronidazole alone, percutaneous aspiration (PA), and percutaneous catheter drainage (PCD) in the treatment of uncomplicated amebic liver abscess (ALA) is still unclear. This systematic review and meta-analysis evaluated the available evidences with regard to treatment modalities in such patients.

METHODS

The database was searched for relevant randomized controlled trials (RCTs) published until May 2019. All studies were assessed for risk of bias. The relevant data were pooled in a random or fixed-effect model to calculate the mean difference (MD) or relative risks.

RESULTS

After the detailed screening, 570 patients from 10 RCTs comparing metronidazole alone with metronidazole + PA were included. Most studies had uncertain risk of biases. Days to resolution of abdominal pain (MD - 1.59, 95% confidence interval [CI] - 2.77, - 0.42, I2 = 89%) and tenderness (MD - 1.76, 95% CI - 2.93, - 0.58, I2 = 72%) were significantly shorter in the metronidazole + PA group. There was no significant difference in relation to the resolution of fever, abscess size, and hospital stay. The beneficial effects of PA were seen with medium-to-large (> 5 cm) ALA and not with small (< 5 cm) ALA. Addition of PCD to metronidazole therapy was better than metronidazole alone in one low-quality RCT. Two RCTs found PCD to be better than PA for large ALA.

CONCLUSIONS

Percutaneous aspiration as compared with metronidazole alone results in the early resolution of pain and tenderness in patients with medium-to-large ALA. Percutaneous catheter drainage is better for larger ALA. However, discrepancies in RCTs create therapeutic dilemmas necessitating further efforts to generate more reliable data.

A Unique Case of Empyema Secondary to Amoebic Liver Abscess

An amoebic liver abscess is an extraintestinal manifestation of amoebiasis that can present with complaints such as right upper quadrant pain and fever. It might not necessarily be associated with abdominal complaints and can have many other atypical presentations. It may present with lung diseases, cardiac diseases, or brain abscesses. We present a case of a patient with empyema secondary to amoebic liver abscess whose diagnosis was delayed due to an unusual presentation. A combination of radiology, serology, and therapeutic interventions led to the accurate management of the patient.