CT of amebic liver abscess: different morphological types with different clinical features

Vascular complications of amebic liver abscess - Computed tomography case series with review of the literature

Amebiasis is a parasitic infection with amebic liver abscess (ALA) being the most common extraintestinal manifestation. Common complications of ALA include rupture into the pleural, pericardial, or peritoneal cavity. Uncommonly, they can cause vascular complications such as thrombosis of the hepatic vein and inferior vena cava which may further extend to the right atrium or may embolize resulting in pulmonary thromboembolism. In this study, we report three patients with vascular complications in ALA. The presence of vascular pathology in ALAs should not be missed. With its detection and prompt treatment, the progression of vascular complications can be prevented.

Comprehensive CT study to assess local and systemic involvement in patients with infective endocarditis: experience from a multidisciplinary team of a tertiary referral center

PURPOSE

To evaluate the value of a computed tomography (CT) protocol, including ECG-gated cardiac angiographic and venous phase, in patients with infective endocarditis (IE).

MATERIAL AND METHODS

From January 2019 to October 2022, consecutive patients with IE submitted to total-body CT, including ECG-gated cardiac acquisition in angiographic and venous phase, were enrolled. Transesophageal echocardiography was performed in all cases. Rate of local complications including vegetation, pseudoaneurysm, abscess, fistula and valve dehiscence was compared in CT and echocardiography. Systemic embolization was identified through CT scans.

RESULTS

Seventy-six adults (median age 69 [IQR 55-77] years old; males 54/76, 71%] were enrolled. Most patients underwent surgery (51/76, 67%), and the in-hospital mortality rate was 8% (6/76). CT showed higher detection rate of valve vegetation compared to echocardiography (67/76, 88% vs 58/76, 76%; p = 0.008), including vegetation smaller than 10 mm (24/76, 36% vs 16/76, 28%; p = 0.013) and higher detection rate of pseudoaneurysm and abscess (p = 0.004 and p = 0.009, respectively). Abscess showed higher contrast-to-noise ratio (CNR) in the venous scan compared to angiographic scan (2.75 [IQR 2.27; 5.17] vs 1.97 [IQR 1.21; 3.32], p = 0.039) and higher density of perivalvular and epicardial fat compared to pseudoaneurysm (35 [IQR 31; 52]HU and - 50 [IQR - 62; - 35]HU versus 52 [IQR - 60; - 18]HU; p = 0.001, and - 91 [IQR - 95; - 81]HU; p = 0.007, respectively), for greater inflammation. CT overestimated valve dehiscence when compared to echocardiography and surgery.

CONCLUSION

A comprehensive CT study enhances the diagnostic assessment of patients with IE, not only by detecting distant sites of embolization, but also increasing sensitivity for valve vegetation and local complications.

Comparative efficacy of contrast-enhanced ultrasound versus B-mode ultrasound in the diagnosis and monitoring of hepatic abscesses

Purpose

This study aimed to evaluate the diagnostic value of contrast-enhanced ultrasound (CEUS) in diagnosing and monitoring hepatic abscesses (HA).

Material and methods

This retrospective study included 29 patients (9 females, 20 males) with 64 HA. Computed tomography (CT) served as the diagnostic benchmark, compared with CEUS and B-mode ultrasound (B-mode). Two radiologists assessed the presence, size, and characteristics of the HA.

Results

The contrast enhancement pattern on CEUS matched post-contrast CT. Lesion size detected by CEUS ranged from 1.16 cm to 15.33 cm (median 5.74 cm). CT classified lesions into four types: I (tumor-like) - 2, II (honeycomb) - 5, III (lacunar) - 23, IV (cystic-like) - 34. CEUS fully agreed with these classifications. B-mode missed two type I lesions. For type III abscesses, agreement with CEUS was perfect (κ = 1, 100%), and moderate with B-mode (κ = 0.50, 79.7%). For type IV abscesses, agreement with CEUS was perfect (κ = 1, 100%), and high with B-mode (κ = 0.88, 93.75%). Pus enhancement remained stable (± 15 dB), while the abscess pouch background varied (± 11 dB to ± 6 dB). The Mann-Whitney U test confirmed these observations (arterial: p = 1.02e-14, portal: p = 3.79e-12, late venous: p = 4.53e-13). No significant difference in enhancement values was found based on abscess size (> 4 cm vs. < 4 cm).

Conclusions

CEUS is superior to B-mode for diagnosing and monitoring HA, offering clearer views of the abscess pouch, septa, and liver parenchyma. The purulent part lacks contrast, allowing accurate assessment. CEUS can replace CT for monitoring and aid in patient selection for percutaneous intervention.

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.

Observational Study of Clinical Profiles and Management of Liver Abscess in Hospitalized Patients: A North Indian Tertiary Care Perspective

Background Liver abscesses are a significant health concern, necessitating prompt diagnosis and appropriate management. Spontaneous liver abscesses are a frequent reason for hospitalizations in India, particularly in the northern part. By analyzing demographics, symptoms, radiological findings, laboratory parameters, and treatment outcomes, this study will contribute valuable insights to enhance the understanding and management of liver abscesses. Aims and objective To evaluate demographic, clinical, laboratory, and radiological parameters and management options in hospitalized patients with liver abscesses at a tertiary care center. Methods This study retrospectively analyzed prospectively collected data from 150 patients diagnosed with liver abscesses who were admitted to our ward for one year. Data on demographic characteristics, clinical presentation, etiology, radiological findings, laboratory investigations, management strategies, and treatment outcomes were collected. Descriptive statistics and relevant statistical tests were employed for data analysis. Results The study population had a mean age of 40.28±12.72 years, with a male preponderance (136 (90.7%)). Amoebic abscesses (94 (62.7%)) were the most common. Hepatomegaly (144 (96%)), fever (140 (93.3%)), abdominal pain (136 (90.7%)), and anorexia (118 (78.7%)) were the most common symptoms. Ultrasonography revealed solitary abscesses (99 (66%)) to be more common than multiple abscesses (24 (16%)), with a predominant location in the right lobe (128 (85.3%)). Laboratory investigations showed leukocytosis in 121 (80.7%), elevated liver enzymes (95 (63.3%) aspartate aminotransferase (AST) and 80 (53.3%) alanine transaminase (ALT)), elevated alkaline phosphatase (ALP) in 133 (88.7%), and low albumin levels (138 (92%)) in a significant proportion of patients. Single-time needle aspiration (95 (63.3%)), percutaneous drain (36 (24%)), and surgical intervention (4 (2.7%)) were the primary treatment modalities. Serum albumin level (p<0.001) and ALP (p<0.001) were significantly low and high, respectively, in patients with hospital stays ≥10 days. Conclusions This study provides insights into patients with liver abscesses' clinical and laboratory parameters and management strategies. The findings highlight the diverse clinical presentation, varied etiologies, and the importance of radiological imaging and laboratory investigations in diagnosis and management. Tailored treatment strategies based on the patient's condition are crucial for optimizing outcomes.

Intestinal Parasitic Infections in 2023

Intestinal parasites include intestinal protozoa and intestinal helminths. Intestinal parasitic infections (IPIs) pose a global health problem affecting over one billion people worldwide. Although these infections are predominantly seen in the developing world, they are frequently seen in the developed countries, particularly in immunocompromised patients. Patients' clinical presentations generally include diarrhea, dysentery, abdominal pain, nausea, vomiting, nutritional deficiency, iron deficiency anemia, anal and perianal itching, and rarely intestinal obstruction. The intestinal parasites have similarities in their mode of transmission and life cycle. The stool test is the primary way of diagnosing IPIs. Treatment is given with various anti-parasitic agents. However, appropriate preventive measures are essential for successfully controlling the IPIs.

Amebic liver abscess by Entamoeba histolytica

Amebic liver abscesses (ALAs) are the most commonly encountered extraintestinal manifestation of human invasive amebiasis, which results from Entamoeba histolytica (E. histolytica) spreading extraintestinally. Amebiasis can be complicated by liver abscess in 9% of cases, and ALAs led to almost 50000 fatalities worldwide in 2010. Although there have been fewer and fewer cases in the past several years, ALAs remain an important public health problem in endemic areas. E. histolytica causes both amebic colitis and liver abscess by breaching the host's innate defenses and invading the intestinal mucosa. Trophozoites often enter the circulatory system, where they are filtered in the liver and produce abscesses, and develop into severe invasive diseases such as ALAs. The clinical presentation can appear to be colitis, including upper-right abdominal pain accompanied by a fever in ALA cases. Proper diagnosis requires nonspecific liver imaging as well as detecting anti-E. histolytica antibodies; however, these antibodies cannot be used to distinguish between a previous infection and an acute infection. Therefore, diagnostics primarily aim to use PCR or enzyme-linked immunosorbent assay to detect E. histolytica. ALAs can be treated medically, and percutaneous catheter drainage is only necessary in approximately 15% of cases. The indicated treatment is to administer an amebicidal drug (such as tinidazole or metronidazole) and paromomycin or other luminal cysticidal agent for clinical disease. Prognosis is good with almost universal recovery. Establishing which diagnostic methods are most efficacious will necessitate further analysis of similar clinical cases.

Amebic liver abscess: Clinico-radiological findings and interventional management

In its classic form, amebic liver abscess (ALA) is a mild disease, which responds dramatically to antibiotics and rarely requires drainage. However, the two other forms of the disease, i.e., acute aggressive and chronic indolent usually require drainage. These forms of ALA are frequently reported in endemic areas. The acute aggressive disease is particularly associated with serious complications, such as ruptures, secondary infections, and biliary communications. Laboratory parameters are deranged, with signs of organ failure often present. This form of disease is also associated with a high mortality rate, and early drainage is often required to control the disease severity. In the chronic form, the disease is characterized by low-grade symptoms, mainly pain in the right upper quadrant. Ultrasound and computed tomography (CT) play an important role not only in the diagnosis but also in the assessment of disease severity and identification of the associated complications. Recently, it has been shown that CT imaging morphology can be classified into three patterns, which seem to correlate with the clinical subtypes. Each pattern depicts its own set of distinctive imaging features. In this review, we briefly outline the clinical and imaging features of the three distinct forms of ALA, and discuss the role of percutaneous drainage in the management of ALA.

Amoebic Liver Abscess: Rare Entity in Recent Times

Intestinal amoebiasis and sequelae such as amoebic liver abscess are rarely reported in the era of modern medicine. Atypical presentation of amoebic liver abscess with high false-positive results on serology in endemic regions poses major diagnostic issues in the developing nations of the world. We report a case of amoebic liver abscess and describe the imaging appearances in a 59-year-old female. A detailed medical history was elicited to determine the etiology of amoebic liver abscess. Furthermore, the diagnosis was confirmed based on serological tests. Percutaneous aspiration of the amoebic liver abscess was performed, and treatment was initiated with intravenous metronidazole followed by diloxanide furoate. The patient has been on follow-up since three months with a negative stool examination and with no complaints of recurrence.