Hepatic involvement in larva migrans of Toxocara canis: report of a case with pathological and radiological findings

Enhanced resolution of eosinophilic liver abscess associated with toxocariasis by albendazole treatment

BACKGROUND/AIMS

Visceral larva migrans, caused by Toxocara canis and Toxocara cati, has emerged as a significant cause of eosinophilic liver abscess (ELA). Differentiation of ELA associated with toxocariasis (ELA-T) from metastasis or primary liver malignancy is sometimes difficult. However, the role of albendazole treatment remains uncertain in this condition. The aim of this study was to evaluate whether albendazole can enhance the radiologic resolution of ELA-T.

METHODS

We retrospectively reviewed the medical records of the patients diagnosed with ELA-T at our institution between January 2008 and December 2011. ELA-T was diagnosed based on the imaging findings on computed tomography or magnetic resonance imaging and the presence of positive serum IgG antibody for Toxocara canis. Among a total of 163 patients, 32 patients received albendazole (albendazole group) and 131 did not (control group). Baseline characteristics and fate of liver nodules were compared between the two groups.

RESULTS

Baseline characteristics (age, sex, number and maximal size of lesions, eosinophil count) were similar between the two groups. Median duration for achieving radiologic resolution in the albendazole group was significantly shorter than in the control group (207 days [range 186-228] vs. 302 days [range 224-380], p=0.023). In Cox regression analysis of the cumulative rates of radiologic resolution, the hazard ratio for albendazole treatment was 1.99 (95% confidence interval, 1.22-3.23).

CONCLUSIONS

Radiologic resolution of ELA-T can be accelerated with albendazole treatment. Hence, inconvenience associated with long-term follow-up and unnecessary worries among patients can be eliminated with albendazole treatment.

Infections of the Liver

The portal vein carries blood from the gastrointestinal tract to the liver and in so doing carries microbes as well. The liver may therefore be involved in infections with a myriad number of microbial organisms. While some of these infections most commonly occur in the immunocompromised host, others affect the immune competence. Hepatic infections may be primary in nature or secondary, as part of systemic or contagious disease. The purpose of this chapter is to provide a brief overview of the various infections of the liver in the pediatric patient.

Significance of Charcot Leyden crystals in hepatic aspirates

Charcot Leyden crystals are hexagonal bipyramidal structures localised in the primary granules of the cytoplasm of eosinophils and basophils. Their presence, along with eosinophilic infiltrate, is an indirect evidence of parasitic infestation particularly with Toxocara, Capilliriasis, Ascariasis, or Fasciola. We report here two cases where Charcot Leyden crystals with eosinophilic infiltrate were found in the smears prepared from hepatic abscess.

A Case of Hypereosinophilia-Associated Multiple Mass Lesions of Liver Showing Non-Granulomatous Eosinophilic Hepatic Necrosis

Hypereosinophilic syndrome (HES) is defined by elevation more than 1.5×10⁹/L of presence of a peripheral blood count, evidence of organ involvement, and exclusion of secondary eosinophilia such as allergic, vasculitis, drugs, or parasite infection and also clonal eosinophilia. We present the HES case with hepatic involvement. The patient is 70-year-old male. He complained fever and back pain. Blood examination showed marked peripheral eosinophilia, elevation of transaminase and biliary enzymes. Multiple irregular mass lesions of the liver were pointed out by CT and MRI. The liver biopsy was done for differentiation from malignancy. In parenchyma, hepatic necrotic lesion was observed accompanying severe eosinophilic infiltration with Charcot-Leyden's crystals. There was granulomatous reaction. He was diagnosed as HES and got recovery due to steroid therapy. From the review of HES article, the hepatic histology is categorized into four types as below: 1) cholangitis type; 2) chronic active hepatitis type; 3) vasculopathic type, 4) hepatic necrosis type. Our case is classified in hepatic necrosis type. This type seems to be important to distinguish malignant tumor and also visceral larva migrans by liver biopsy.

Neurotoxocarosis

Infection of humans with embryonated eggs of Toxocara canis (larva migrans) remains asymptomatic, or results in covert or common toxocarosis, visceral larva migrans syndrome, or ophthalmologic and neurologic impairment. Though neurological manifestations of Toxocara canis larvae are rare, toxocarosis remains an important differential diagnosis of various neurological disorders. Manifestations of the central nervous system are dementia, meningo-encephalitis, myelitis, cerebral vasculitis, epilepsy, or optic neuritis. Manifestations of the peripheral nervous system comprise radiculitis, affection of cranial nerves, or musculo-skeletal involvement. If toxocarosis is neglected, ignored, or refused as a differential of these abnormalities, it may be easily overlooked for years. Early recognition and treatment of the infection is, however, of paramount importance since it reduces morbidity and mortality and the risk of secondary superinfection. Like the visceral manifestations, neurological manifestations of toxocarosis are treated by benzimidazole components, most frequently albendazole, corticosteroids, or diethylcarbamazine. If detected and treated early, the prognosis of neurological manifestations of toxocarosis is favourable.

Rho/Rho kinase is a key enzyme system involved in the angiotensin II signaling pathway of liver fibrosis and steatosis

BACKGROUND AND AIM

The molecular mechanisms underlying the involvement of the renin-angiotensin system in hepatic fibrosis are unclear. Recently, it was reported that a Rho kinase inhibitor prevented fibrosis of various tissues and that the Rho/Rho kinase pathway was involved in the renin-angiotensin system of vascular smooth muscle cells. In this study, the involvement of the Rho/Rho kinase pathway on angiotensin II signaling in liver fibrogenesis and generation of steatosis was investigated.

METHODS

Rats were fed a choline-deficient/L-amino acid-defined (CDAA) diet continuously and treated with a Rho kinase inhibitor, Y-27632, and an angiotensin II receptor blocker, TCV-116. Liver histology and hepatic stellate cell activation were analyzed. Free radical production was detected by 4-hydroxynonenal and 8-hydroxy-2'-deoxyguanosine immunostaining and the expression of tumor necrosis factor-alpha was examined. Isolated hepatic stellate cells were pretreated with a Rho kinase inhibitor, Y-27632, or an angiotensin II receptor blocker, CV-11974, and stimulated with angiotensin II, and mRNA expression of transforming growth factor-beta and alpha-smooth muscle actin was analyzed.

RESULTS

Both the angiotensin II receptor blocker and the Rho kinase inhibitor improved fibrosis and steatosis of the liver in CDAA-fed rats. The increase in the number of hepatocytes positive for 4-hydroxynonenal and 8-hydroxy-2'-deoxyguanosine in CDAA-fed rats was significantly prevented by the angiotensin II receptor blocker and the Rho kinase inhibitor. The levels of tumor necrosis factor-alpha mRNA in the liver of CDAA-fed rats were significantly increased and this increase was significantly inhibited by treatment with the angiotensin II receptor blocker and the Rho kinase inhibitor. mRNA expression of transforming growth factor-beta and alpha-smooth muscle actin stimulated by angiotensin II was also significantly suppressed by these two drugs.

CONCLUSION

These results suggest that the Rho/Rho kinase pathway is at least partly involved in the renin-angiotensin system and plays an important role in hepatic fibrosis and steatosis.