A Giant Scrotal Neurofibroma in a Child Masquerading as Filariasis: Uncommon Presentation of a Common Disease

Neurofibroma of the scrotum is a very uncommon benign neoplasm, specifically when it affects teenagers and is not associated with neurofibromatosis type I. To the best of our knowledge, only a couple of cases of neurofibroma in children have been documented. Here, we report a case study of a 17-year-old boy who had a giant scrotal lump for ten years masquerading clinically as filariasis. A provisional diagnosis of benign nerve sheath neoplasm was made based on cytology findings. The lump was surgically removed from the patient, and a histopathological and immunohistochemistry examination established the diagnosis of neurofibroma. The combined clinical, preoperative cytological, histological, and immunohistochemistry findings were not presented in the literature in any of the formerly documented cases of scrotal neurofibroma. The current case expands the spectrum of differential diagnoses for scrotal tumours that clinicians have previously observed.

Individuals co-exposed to sand fly saliva and filarial parasites exhibit altered monocyte function

BACKGROUND

In Mali, cutaneous leishmaniasis (CL) and filariasis are co-endemic. Previous studies in animal models of infection have shown that sand fly saliva enhance infectivity of Leishmania parasites in naïve hosts while saliva-specific adaptive immune responses may protect against cutaneous and visceral leishmaniasis. In contrast, the human immune response to Phlebotomus duboscqi (Pd) saliva, the principal sand fly vector in Mali, was found to be dichotomously polarized with some individuals having a Th1-dominated response and others having a Th2-biased response. We hypothesized that co-infection with filarial parasites may be an underlying factor that modulates the immune response to Pd saliva in endemic regions.

METHODOLOGY/PRINCIPAL FINDINGS

To understand which cell types may be responsible for polarizing human responses to sand fly saliva, we investigated the effect of salivary glands (SG) of Pd on human monocytes. To this end, elutriated monocytes were cultured in vitro, alone, or with SG, microfilariae antigen (MF ag) of Brugia malayi, or LPS, a positive control. The mRNA expression of genes involved in inflammatory or regulatory responses was then measured as were cytokines and chemokines associated with these responses. Monocytes of individuals who were not exposed to sand fly bites (mainly North American controls) significantly upregulated the production of IL-6 and CCL4; cytokines that enhance leishmania parasite establishment, in response to SG from Pd or other vector species. This selective inflammatory response was lost in individuals that were exposed to sand fly bites which was not changed by co-infection with filarial parasites. Furthermore, infection with filarial parasites resulted in upregulation of CCL22, a type-2 associated chemokine, both at the mRNA levels and by its observed effect on the frequency of recruited monocytes.

CONCLUSIONS/SIGNIFICANCE

Together, our data suggest that SG or recombinant salivary proteins from Pd alter human monocyte function by upregulating selective inflammatory cytokines.

A cross-sectional study of the filarial and Leishmania co-endemicity in two ecologically distinct settings in Mali

BACKGROUND

Filariasis and leishmaniasis are two neglected tropical diseases in Mali. Due to distribution and associated clinical features, both diseases are of concern to public health. The goal of this study was to determine the prevalence of co-infection with filarial (Wuchereria bancrofti and Mansonella perstans) and Leishmania major parasites in two ecologically distinct areas of Mali, the Kolokani district (villages of Tieneguebougou and Bougoudiana) in North Sudan Savanna area, and the district of Kolondieba (village of Boundioba) in the South Sudan Savanna area.

METHODS

The prevalence of co-infection (filarial and Leishmania) was measured based on (i) Mansonella perstans microfilaremia count and/or filariasis immunochromatographic test (ICT) for Wuchereria bancrofti-specific circulating antigen, and (ii) the prevalence of delayed type hypersensitivity (DTH) responses to Leishmania measured by leishmanin skin test (LST).

RESULTS

In this study, a total of 930 volunteers between the age of 18 and 65 were included from the two endemic areas of Kolokani and Kolondieba. In general, in both areas, filarial infection was more prevalent than Leishmania infection with an overall prevalence of 15.27% (142/930) including 8.7% (81/930) for Mansonella perstans and 8% (74/930) for Wuchereria bancrofti-specific circulating antigen. The prevalence of Leishmania major infection was 7.7% (72/930) and was significantly higher in Tieneguebougou and Bougoudiana (15.05%; 64/425) than in Boundioba (2.04%; 8/505) (χ2 = 58.66, P < 0.0001). Among the filarial infected population, nearly 10% (14/142) were also positive for Leishmania with an overall prevalence of co-infection of 1.50% (14/930) varying from 2.82% (12/425) in Tieneguebougou and Bougoudiana to 0.39% (2/505) in Boundioba (P = 0.0048).

CONCLUSION

This study established the existence of co-endemicity of filarial and Leishmania infections in specific regions of Mali. Since both filarial and Leishmania infections are vector-borne with mosquitoes and sand flies as respective vectors, an integrated vector control approach should be considered in co-endemic areas. The effect of potential interaction between filarial and Leishmania parasites on the disease outcomes may be further studied.

Malignant Pleural Effusion with Filariasis

The occurrence of microfilaria in pleural fluid is rare. Filarial lung involvement occurs in the form of Tropical Pulmonary Eosinophilia with pulmonary infiltrates and peripheral eosinophilia. We report a 74-year-old male patient, non smoker who was admitted to our hospital with breathlessness and chest discomfort of two weeks duration. He had, eosinophilia and deranged renal function. X-ray chest revealed massive left sided pleural effusion. Pleural fluid analysis revealed atypical cells and pleural fluid cytology showed microfilaria (Wuchereria bancrofti), which were also found on peripheral smear.

[Effect of comprehensive care for chronic filariasis patients with lymphedema]

OBJECTIVE

To evaluate the effect of chronic filariasis patients with lymphedema after comprehensive cared.

METHODS

A total of 386 chronic filariasis patients with lymphedema received the comprehensive care including soaking feet by TCM, washing feet by single Chinese medicine or clear water, preventing and eliminating invasive wound, physical training, raising the limb, and wearing suitable shoes. The attack frequency of inflammation of lymphatic vessels, the stage of lymphedema disease, and leg circumference were observed before and after the care.

RESULTS

After the comprehensive care, the attack rates of inflammation of lymphatic vessels decreased from 9.65% to 4.67%, and there was a significant difference (χ2 =7.34, P=0.0067). The proportion of the patients with high stage of lymphedema disease decreased significantly (all P <0.01), and the average leg circumference decreased of 1.06 cm. The skin appearance improved significantly. Other signs, such as pitting edema, ulcer, and skin folds also improved significantly (all P <0.01).

CONCLUSION

The comprehensive care for chronic filariasis patients with lymphedema has a remarkable effect and is worthy of further application.

Filarial chyluria as a rare cause of urinary retention

We herein describe a case of Wuchereria bancrofti infection in a previously healthy 37-year-old Nepalese man. The patient presented with a history of milky urine with subsequent acute urinary retention lasting for a few days. The presence of microfilariae was confirmed on both peripheral blood and urine smears obtained at midnight. He was conservatively treated with diethylcarbamazine combined with doxycycline. Filariasis was previously endemic in southern parts of Japan, although it has been eradicated. Clinicians should remember filariasis as a potential etiology of urinary retention, especially in cases that may be associated with imported infectious disease.

Chronic helminth infection does not exacerbate Mycobacterium tuberculosis infection

Background

Chronic helminth infections induce a Th2 immune shift and establish an immunoregulatory milieu. As both of these responses can suppress Th1 immunity, which is necessary for control of Mycobacterium tuberculosis (MTB) infection, we hypothesized that chronic helminth infections may exacerbate the course of MTB.

Methodology/Principal Findings

Co-infection studies were conducted in cotton rats as they are the natural host for the filarial nematode Litomosoides sigmodontis and are an excellent model for human MTB. Immunogical responses, histological studies, and quantitative mycobacterial cultures were assessed two months after MTB challenge in cotton rats with and without chronic L. sigmodontis infection. Spleen cell proliferation and interferon gamma production in response to purified protein derivative were similar between co-infected and MTB-only infected animals. In contrast to our hypothesis, MTB loads and occurrence and size of lung granulomas were not increased in co-infected animals.

Conclusions/Significance

These findings suggest that chronic filaria infections do not exacerbate MTB infection in the cotton rat model. While these results suggest that filaria eradication programs may not facilitate MTB control, they indicate that it may be possible to develop worm-derived therapies for autoimmune diseases that do not substantially increase the risk for infections.

Tuberculosis prevalence is high in areas that are endemic for helminths, suggesting that many people are chronically infected with both pathogens. As parasitic helminths can suppress the host immune system to facilitate their own survival, they frequently impact the host immune response to bystander antigens. Thus, while helminth infections ameliorate allergies and autoimmune diseases, they also decrease immune responses elicited by vaccines. Several studies have shown that helminth exposure impairs Mycobacterium tuberculosis-specific immune responses, raising the possibility that helminth infections may decrease the host's ability to control M. tuberculosis infection. To test this, we analyzed whether chronic infection of cotton rats with the filarial worm Litomosoides sigmodontis exacerbates the course of M. tuberculosis infection. Cotton rats are an excellent model organism to study human M. tuberculosis as they develop, in contrast to mice, distinct granuloma formation during infection. In addition, cotton rats are the natural host for L. sigmodontis, a nematode that establishes long-lived infections (>2 years) with circulating microfilariae in these animals. The results of this study demonstrate that chronic filarial infection does not exacerbate M. tuberculosis-associated pathology or mycobacterial burdens in cotton rats and suggest that filaria-induced immunoregulation can be overcome to respond effectively to newly acquired infections.

Worms, not germs

We present a case of a recent immigrant from India with 8 weeks of respiratory symptoms, eosinophilia, and diffuse reticulonodular opacity on chest X-ray. Further investigation revealed the cause to be tropical filarial pulmonary eosinophilia, for which he was successfully treated. We discuss the clinical features, investigation, and aetiology of this condition, which should be considered in patients from endemic areas.

Filariasis attenuates anemia and proinflammatory responses associated with clinical malaria: a matched prospective study in children and young adults

Background

Wuchereria bancrofti (Wb) and Mansonella perstans (Mp) are blood-borne filarial parasites that are endemic in many countries of Africa, including Mali. The geographic distribution of Wb and Mp overlaps considerably with that of malaria, and coinfection is common. Although chronic filarial infection has been shown to alter immune responses to malaria parasites, its effect on clinical and immunologic responses in acute malaria is unknown.

Methodology/Principal Findings

To address this question, 31 filaria-positive (FIL+) and 31 filaria-negative (FIL−) children and young adults, matched for age, gender and hemoglobin type, were followed prospectively through a malaria transmission season. Filarial infection was defined by the presence of Wb or Mp microfilariae on calibrated thick smears performed between 10 pm and 2 am and/or by the presence of circulating filarial antigen in serum. Clinical malaria was defined as axillary temperature ≥37.5°C or another symptom or sign compatible with malaria infection plus the presence of asexual malaria parasites on a thick blood smear. Although the incidence of clinical malaria, time to first episode, clinical signs and symptoms, and malaria parasitemia were comparable between the two groups, geometric mean hemoglobin levels were significantly decreased in FIL− subjects at the height of the transmission season compared to FIL+ subjects (11.4 g/dL vs. 12.5 g/dL, p<0.01). Plasma levels of IL-1ra, IP-10 and IL-8 were significantly decreased in FIL+ subjects at the time of presentation with clinical malaria (99, 2145 and 49 pg/ml, respectively as compared to 474, 5522 and 247 pg/ml in FIL− subjects).

Conclusions/Significance

These data suggest that pre-existent filarial infection attenuates immune responses associated with severe malaria and protects against anemia, but has little effect on susceptibility to or severity of acute malaria infection. The apparent protective effect of filarial infection against anemia is intriguing and warrants further study in a larger cohort.

In many regions of the world, including sub-Saharan Africa, concomitant infection with multiple parasites is common. In order to examine the effects of filariasis, a chronic helminth infection, on immune responses and clinical manifestations of acute malaria infection, the authors followed 31 filaria-infected (FIL+) and 31 filaria-uninfected (FIL–) individuals living in a malaria-endemic area of Mali through an entire malaria transmission season for the development of clinical malaria (fever or other symptoms of malaria in the setting of detectable blood parasites). Serum levels of inflammatory cytokines previously associated with severe malaria were decreased in FIL+ subjects at the time of acute clinical malaria. Although there were no differences between FIL+ and FIL– subjects with respect to the time of first episode of malaria or the number or severity of malaria episodes, filarial infection appeared to protect against the development of anemia during the malaria transmission season. These findings demonstrate that chronic filarial infection modulates the immune response to acute malaria. The apparent effect on anemia is intriguing and deserves further study.

Microfilariae in lymph node aspirate associated with metastatic gastric carcinoma: a case report

BACKGROUND

Microfilariae of Wuchereria bancrofti inhabit peripheral blood, and nocturnal periodicity is observed in the Indian subcontinent. However, microfilariae have been reported in various tissues and organs by needle aspiration cytology in atypical cases. Occasionally, they were detected in cases with some diseases including malignancy.

CASE

A 55-year-old man presented with complaints of weakness, abdominal distention and anorexia for 3 months. He had pain in the upper abdomen, passage of blackish stool and an episode of hemoptysis later on. A provisional diagnosis of gastric carcinoma with cirrhosis and ascites was made. Aspiration cytology of the left supraclavicular lymph node revealed a microfilaria in the background of malignant cells. Biopsy of the antral mass confirmed the diagnosis of gastric carcinoma.

CONCLUSION

Detection of a microfilaria with malignant cells in the lymph node aspirates in a case of gastric carcinoma as an incidental finding is being reported for the first time. It may be due to its transmigration along with metastatic emboli in an immunosuppressed state.

Filariasis: an emergent cause of acute scrotal pain

A 25-year-old man from Bangla Desh with acute right scrotal pain was subjected to scrotal surgical exploration because of the suspicion of testicular torsion. The testicle appeared normally positioned; an epididymal nodule was removed, and pathology showed the presence of the filaria worm. Filariasis is a tropical disease which has been estimated to affect 120 millions people throughout the world. Lymphadenitis and lymphangitis are the more common clinical settings; in men, there is a frequent scrotal involvement. In some cases, acute scrotal pain may lead to the suspicion of testicular torsion. The observation of patients with genital filariasis is likely to become more frequent in an era of massive immigration from different countries; nowadays, the disease should always be taken into consideration in the differential diagnosis in patients with acute scrotal pain coming from tropical areas.

Antibody isotype analysis of malaria-nematode co-infection: problems and solutions associated with cross-reactivity

BACKGROUND

Antibody isotype responses can be useful as indicators of immune bias during infection. In studies of parasite co-infection however, interpretation of immune bias is complicated by the occurrence of cross-reactive antibodies. To confidently attribute shifts in immune bias to the presence of a co-infecting parasite, we suggest practical approaches to account for antibody cross-reactivity. The potential for cross-reactive antibodies to influence disease outcome is also discussed.

RESULTS

Utilising two murine models of malaria-helminth co-infection we analysed antibody responses of mice singly- or co-infected with Plasmodium chabaudi chabaudi and Nippostrongylus brasiliensis or Litomosoides sigmodontis. We observed cross-reactive antibody responses that recognised antigens from both pathogens irrespective of whether crude parasite antigen preparations or purified recombinant proteins were used in ELISA. These responses were not apparent in control mice. The relative strength of cross-reactive versus antigen-specific responses was determined by calculating antibody titre. In addition, we analysed antibody binding to periodate-treated antigens, to distinguish responses targeted to protein versus carbohydrate moieties. Periodate treatment affected both antigen-specific and cross-reactive responses. For example, malaria-induced cross-reactive IgG1 responses were found to target the carbohydrate component of the helminth antigen, as they were not detected following periodate treatment. Interestingly, periodate treatment of recombinant malaria antigen Merozoite Surface Protein-119 (MSP-119) resulted in increased detection of antigen-specific IgG2a responses in malaria-infected mice. This suggests that glycosylation may have been masking protein epitopes and that periodate-treated MSP-119 may more closely reflect the natural non-glycosylated antigen seen during infection.

CONCLUSIONS

In order to utilize antibody isotypes as a measure of immune bias during co-infection studies, it is important to dissect antigen-specific from cross-reactive antibody responses. Calculating antibody titre, rather than using a single dilution of serum, as a measure of the relative strength of the response, largely accomplished this. Elimination of the carbohydrate moiety of an antigen that can often be the target of cross-reactive antibodies also proved useful.

Attenuation of toll-like receptor expression and function in latent tuberculosis by coexistent filarial infection with restoration following antifilarial chemotherapy

Mycobacterium tuberculosis (Mtb) and filarial coinfection is highly prevalent, and the presence of filarial infections may regulate the Toll-like receptor (TLR)-dependent immune response needed to control Mtb infection. By analyzing the baseline and mycobacterial antigen–stimulated expression of TLR1, 2, 4, and 9 (in individuals with latent tuberculosis [TB] with or without filarial infection), we were able to demonstrate that filarial infection, coincident with Mtb, significantly diminishes both baseline and Mtb antigen-specific TLR2 and TLR9 expression. In addition, pro-inflammatory cytokine responses to TLR2 and 9 ligands are significantly diminished in filaria/TB-coinfected individuals. Definitive treatment of lymphatic filariasis significantly restores the pro-inflammatory cytokine responses in individuals with latent TB. Coincident filarial infection exerted a profound inhibitory effect on protective mycobacteria-specific TLR-mediated immune responses in latent tuberculosis and suggests a novel mechanism by which concomitant filarial infections predispose to the development of active tuberculosis in humans.

Lymphatic filariasis afflicts over 120 million people worldwide, while Mycobacterium tuberculosis infects over 2 billion people worldwide. Almost 90% of infected people harbor latent tuberculosis infection with no clinical manifestations. Toll-like receptors (TLRs), pattern-recognition receptors that are present on host immune cells, constitute an important facet of host immune response initiation against a variety of pathogens. Because lymphatic filariasis and tuberculosis are co-endemic in many parts of the world and because TLR modulation is an important feature of both infections, we examined the effect of coexisting filarial infection on TLR-specific immune responses in latent tuberculosis by comparing cellular immune responses to Toll ligands in individuals with latent tuberculosis with or without concomitant lymphatic filariasis. We first examined modulation of TLRs at the gene expression level and determined that downregulation of TLR2 and 9 is associated with coexisting filarial infection. We then determined that Toll ligand-induced pro-inflammatory cytokine production—which is crucial in host defense against TB—is diminished in the presence of filarial coinfection. Treatment of filarial infection restores cytokine production in individuals with latent TB. Thus, we conclude that coexisting filarial infections might significantly compromise essential immune responses in tuberculosis and that treatment of filarial infections would potentially confer tremendous benefit in combating tuberculosis.

Reduction in levels of plasma vascular endothelial growth factor-A and improvement in hydrocele patients by targeting endosymbiotic Wolbachia sp. in Wuchereria bancrofti with doxycycline

The treatment for hydrocele is expensive, invasive surgery-hydrocelectomy. A drug that could prevent or improve this condition could replace or supplement hydrocelectomy. In Ghana, 42 hydrocele patients participated in a double-blind, placebo-controlled trial of a six-week regimen of doxycycline, 200 mg/day. Four months after doxycycline treatment, patients received 150 mug/kg of ivermectin and 400 mg of albendazole, which is used for mass chemotherapy in this area. Patients were monitored for levels of Wolbachia sp., microfilaremia, antigenemia, plasma levels of vascular endothelial growth factor-A (VEGF-A) and stage/size of the hydrocele. Wolbachia sp. loads/microfilaria, microfilaremia, and antigenemia were significantly reduced in the doxycycline-treated patients compared with the placebo group. The mean plasma levels of VEGF-A were decreased significantly in the doxycycline-treated patients who had active infection. This finding preceded the reduction of the stage of hydrocele. A six-week regimen of doxycycline treatment against filariasis showed amelioration of pathologic conditions of hydrocele patients with active infection.

Simulation models examining the effect of Brugian filariasis on dengue epidemics

Concurrent ingestion of microfilariae (mf) and arboviruses by mosquitoes can enhance the transmission of virus compared with when virus is ingested alone. We studied the effect of mf enhancement on the extrinsic incubation period (EIP) of dengue 1 virus within Aedes aegypti mosquitoes by feeding mosquitoes on blood that either contained virus plus Brugia malayi mf or virus only. Mosquitoes were sampled over time to determine viral dissemination rates. Co-ingestion of mf and virus reduced viral EIP by over half. We used the computer simulation program, DENSiM, to compare the predicted patterns of dengue incidence that would result from such a shortened EIP versus the EIP derived from the control (i.e., virus only) group of mosquitoes. Results indicated that, over the 14-year simulation period, mf-induced acceleration of the EIP would generate more frequent (but not necessarily more severe) epidemics. Potential interactions between arboviruses and hematozoans deserve closer scrutiny.

Filarial/human immunodeficiency virus coinfection in urban southern India

The disease course of human immunodeficiency virus (HIV) is often altered by existing or newly acquired coinfections. Treatment or prevention of these concomitant infections often improves the quality and duration of life of HIV-infected persons. The impact of helminth infections on infections with HIV is less clear. However, HIV is frequently most problematic in areas where helminth infections are common. In advance of the widespread distribution of drugs for elimination of lymphatic filariasis, we assessed the prevalence of active Wuchereria bancrofti infection among HIV-positive patients in Chennai, India at two time points separated by four years. We found that the overall prevalence of W. bancrofti infections among HIV-positive persons was 5-9.5%, and there were no quantitative differences in circulating filarial antigen levels between HIV-positive and HIV-negative filarial-infected patients.

Cytological diagnosis of bancroftian filariasis in lesions clinically anticipated as neoplastic

Filariasis is a common disabling parasitic disease in this region and cytological diagnosis is often not required. Cytology has important role in diagnosis of sub-clinical filariasis. Most cases of cytologically diagnosed filariasis are clinically unanticipated. Microfilaria, ova and fragments of adult worm of Wuchereria bancrofti, in exfoliative as well as aspiration cytology have been reported and are useful in cytological detection of bancroftian filariasis. Microfilaria is frequently detected in association with neoplasm, although the role in tumorogenesis is controversial. The objective of the study was to investigate importance of cytology in diagnosis of filariasis in lesions clinically anticipated to be of neoplastic and to review the cytomorphology of bancroftian filaria and its association with neoplasm. This is a retrospective study carried out in cytology department of Tribhuvan University Teaching Hospital. 14 cases of cytological specimen out of 4291 (0.3%) showed microfilaria; 12 cases were from FNAC from different sites and 2 cases were from pleural fluid. 2 cases showed ova in addition to microfilaria and one of them in addition showed fragment of adult worm. Microfilaria in 4 cases of FNAC and one case ofpleural fluid were associated with malignant cells.

Chyluria with proteinuria or filarial nephropathy? An enigma

Lymphatic filariasis is endemic in India. Out of 128 million infected individuals worldwide, India accounts for 48 million cases [Manson's Tropical Diseases, 21st Ed. p 1488]. Filariasis can have protean manifestations, but Tropical pulmonary eosinophilia and chyluria are unusual manifestations reported mainly from South Asian countries [Manson's Tropical Diseases, 21st Ed. p 1494]. Chyluria occurs only in 2% of filarial afflicted patients in the filarial belt [Diamond E, Schapira HE. Chyluria--a review of literature. Urology 1985;26(5): 427-31]. Lymphatic filariasis presenting as chyluria may be equally rare. Predominant chyluria with no overt lymphatic filariasis remains an enigma.

Cardiac manifestations of parasitic infections part 3: pericardial and miscellaneous cardiopulmonary manifestations

This is part three of a three-part series discussing parasites of the heart. In this section, we present an overview on parasitic diseases involving predominantly the pericardium and other miscellaneous cardiopulmonary manifestations such as some pulmonary hypertension syndromes and endomyocardial fibrosis.

Persistent corneal edema secondary to presumed dead adult filarial worm in the anterior chamber

We present three cases of persistent corneal edema secondary to presumed dead adult filarial worms lying in the anterior chamber with their attachment to the endothelium. Two of them were initially diagnosed as descemet's fold with corneal edema. Two patients underwent penetrating keratoplasty and in one case, surgical removal was partly possible with clearing of cornea.

Clinico-laboratory profile of 45 filarial arthritis cases

This prospective observational study was done during the period from January 2000 to December 2004 including 45 cases of lymphatic filariasis manifested with acute arthritis. Different investigations were carried out to exclude allergy, parasitic and infectious diseases, autoimmune disorder and malignancy. They were given standard treatment with oral non-steroidal anti-inflammatory drugs (NSAIDs). Articular symptoms were not relived satisfactorily. Later they were given oral corticosteroids. During treatment slight relief of symptoms were noted, but all sign-symptoms reappear after withdrawal of corticosteroid drugs. Treatment with oral diethylcarbamazine citrate (DEC) (150 mg/day) for 3 weeks showed complete resolution of arthritis. No side effects or relapse were encountered. The basic mechanism of relief of pain remains unknown. It was assumed that during benign course of lymphatic filariasis, development of arthritis result most likely due to reaction against some occult agents in the joints.

Successful treatment of chyluria, glomerular and tubular abnormalities in a young lady with silver nitrate instillation

A 21- year-old lady presented with chyluria, severe malnutrition, secondary amenorrhea, profound hypoalbuminemia, heavy proteinuria and renal tubular abnormalities suggestive of Type IV renal tubular acidosis. No particular cause for chyluria could be ascertained. She was successfully treated with an injection of 2% silver nitrate into the left ureter and urinary bladder. She continues to be well after 15 years of follow-up.

[Filariasis]

Filariasis are vector-transmitted parasitoses, exclusively tropical, except for dirofilariosis. Their impact differs according to the type of filaria and the induced immune response. The diagnosis is made based on the presence of dermatological or lymphatic manifestations, acute or chronic, associated with usually extended stays in an endemic country. It can also be established following a laboratory examination revealing hypereosinophilia or correspond to the incidental finding of microfilariae (blood or skin). The visualization of the embryonic and/or adult parasite confirms the infection. For pathogenic filariasis with microfilaremiae, paradoxically, clinically positive subjects are often amicrofilaremic. In this case, the presence of antibodies and/or specific serum antigens confirms the diagnosis. On the contrary, asymptomatic microfilariaecarriers are common but there is no guarantee that they will remain asymptomatic. The etiological treatment of choice is based on a combination of ivermectin and albendazole. However, diethylcarbamazine, which was formerly used, is still indicated. Dracunculiasis has been almost eradicated and the elimination of lymphatic filariasis and onchocerciasis as public health problems can be contemplated in the medium term.

Microfilariae in bone marrow aspiration smears, correlation with marrow hypoplasia: a report of six cases

Microfilariae have been reported in various cytological preparations, however there are very few case reports describing microfilariae in bone marrow aspirates. We report six such cases with the interesting finding of marrow hypoplasia in five of these cases.

Filariasis infection is a probable cause of implantation failure in in vitro fertilization cycles

OBJECTIVE

To describe a parasitic infection that probably affected the implantation of good-quality embryos in an in vitro fertilization (IVF) cycle.

DESIGN

Case report.

SETTING

Tertiary care center in a university hospital.

PATIENT(S)

A 36-year-old Caucasian female with primary unexplained infertility. The patient underwent two cycles of IVF with good-quality embryos transferred; however, no pregnancy ensued despite adequate luteal support.

INTERVENTION(S)

In vitro fertilization cycles, CBC, blood smear, evaluation for eosinophilia including serological evaluation for parasitic infections.

MAIN OUTCOME MEASURE(S)

Pregnancy.

RESULT(S)

Following treatment for filariasis, a repeat IVF cycle using the same stimulation protocol yielded a full-term pregnancy.

CONCLUSION(S)

This case is of particular importance because, to our knowledge, it is the first to describe a parasitic infection that probably affected the implantation of good-quality embryos in IVF cycles.

Coincident filarial, intestinal helminth, and mycobacterial infection: helminths fail to influence tuberculin reactivity, but BCG influences hookworm prevalence

The prevalence of helminth and tuberculosis infections is high in South India, whereas Bacille-Calmette-Guerin (BCG) vaccine efficacy is low. Our aim was to determine whether concurrent helminth infection alters the ability to mount a delayed-type hypersensitivity response to tuberculin. In a cross-sectional study in southern India, individuals 6-65 years of age were screened for intestinal helminths, circulating filarial antigenemia, tuberculin reactivity, active tuberculosis, and history of BCG vaccination; 54% were purified protein derivative (PPD) positive, 32% had intestinal helminth infection, 9% were circulating filarial antigen positive, and 0.5% had culture-confirmed active tuberculosis. Only age and BCG vaccination were significantly associated with PPD reactivity; however, BCG vaccination was associated with a lower prevalence of hookworm infection relative to those without prior BCG vaccination. Neither intestinal helminth infection nor filarial infection was associated with diminished frequencies of PPD positivity. Our findings suggest that preceding helminth infection does not influence significantly the delayed-type hypersensitivity response to tuberculin.

Verminous pneumonia due to Filaroides hirthi in a Scottish terrier in Spain

A previously healthy Scottish terrier developed verminous pneumonia due to Filaroides hirthi. The disease was diagnosed on the basis of cytology of a transtracheal wash, which contained 17 per cent eosinophils and a large number of parasite larvae. Treatment with 50 mg/kg bodyweight fenbendazole daily for three weeks eliminated the parasites and improved the clinical condition of the dog.

RENAL PEDICLE LYMPHATIC DISCONNECTION FOR CHYLURIA VIA RETROPERITONEOSCOPY AND OPEN SURGERY: REPORT OF 53 CASES WITH FOLLOWUP

PURPOSE

We present our experience with retroperitoneoscopic renal pedicle lymphatic disconnection. We compared the clinical efficacy of this treatment for chyluria with that of open surgery.

MATERIALS AND METHODS

From January 1998 to June 2004, 53 patients (55 renal units) with chyluria underwent renal pedicle lymphatic disconnection via the retroperitoneoscopic and conventional open approaches. The diagnosis of chyluria was confirmed by the ether test and the side of chylous reflux was determined by cystoscopy. Operative time, intraoperative blood loss, postoperative intestinal recovery and hospital stay were evaluated. Increases in hemoglobin and serum albumin were compared before and after surgery during followup.

RESULTS

Retroperitoneoscopic renal pedicle lymphatic disconnection or open surgery was performed successfully in all patients. In terms of operative time, intraoperative blood loss, postoperative intestinal recovery and hospital stay retroperitoneoscopy was superior to conventional open surgery. During retroperitoneoscopy the inferior vena cava was injured in 1 case but repaired successfully by laparoscopy without conversion to open surgery. Postoperative gross hematuria in 1 case disappeared 4 days later. In the open surgery group the renal segmental artery was inadvertently injured in 1 case and anastomosis was performed successfully. Wound healing was delayed in 1 case due to hypoalbuminemia. Recurrence developed in 2 patients during the 6 to 84-month followup.

CONCLUSIONS

Retroperitoneoscopic renal pedicle lymphatic disconnection for chyluria has the advantages of minimal invasion and rapid recovery compared with open surgery.

The effect of eight half-yearly single-dose treatments with DEC on Wuchereria bancrofti circulating antigenaemia

The effect of eight half-yearly treatment rounds with diethylcarbamazine (DEC; 6mg/kg bodyweight) on Wuchereria bancrofti-specific circulating filarial antigen (CFA), a marker of adult worm infection, was followed in 79 individuals who were CFA-positive before start of treatment. Half of these were also microfilariae (mf)-positive. Microfilaraemia decreased rapidly after onset of treatment and became undetectable after four treatments. Circulating antigenaemia also decreased progressively, but at a much slower rate. After two, four and eight treatment rounds, the mean CFA intensity was reduced by 81, 94 and 98%, and the prevalence of CFA positivity was 85, 66 and 57%, compared with pre-treatment, respectively. CFA clearance rates were negatively related to pre-treatment CFA intensities, and were higher among pre-treatment mf-negative individuals than among pre-treatment mf-positive individuals. Even among patients who had pre-treatment CFA intensities above the upper measuring level (32000antigen units), and who continued to have intensities above this level after treatment, a decrease in post-treatment CFA intensities was obvious from a continuous decrease in ELISA optical density values. Repeated DEC therapy thus appears to have a slow but profound and persistent macrofilaricidal effect, which in the long run may be beneficial to populations undergoing DEC-based control interventions by reducing the probability of future morbidity development.

Co-infected C57BL/6 mice mount appropriately polarized and compartmentalized cytokine responses to Litomosoides sigmodontis and Leishmania major but disease progression is altered

This study examines the capacity of the mammalian host to fully compartmentalize the response to infection with type 1 vs. type 2 inducing organisms that infect different sites in the body. For this purpose, C57BL/6 mice were infected with the rodent filarial nematode Litomosoides sigmodontis followed by footpad infection with the protozoan parasite Leishmania major. In this host, nematode infection is established in the thoracic cavity but no microfilariae circulate in the bloodstream. We utilized quantitative ELISPOT analysis of IL-4 and IFN-gamma producing cells to assess cytokine bias and response magnitude in the lymph nodes draining the sites of infection as well as more systemic responses in the spleen and serum. Contrary to other systems where co-infection has a major impact on bias, cytokine ratios were unaltered in either local lymph node. The most notable effect of co-infection was an unexpected increase in the magnitude of the IFN-gamma response to L. major in mice previously infected with L. sigmodontis. Further, lesion development was significantly delayed in these mice. Thus, despite the ability of the immune system to appropriately compartmentalize the immune response, interactions between responses at distinct infection sites can alter disease progression.

Genetic polymorphisms of eosinophil-derived neurotoxin and eosinophil cationic protein in tropical pulmonary eosinophilia

Because eosinophil-derived neurotoxin (EDN) and eosinophil cationic protein (ECP) are critical in the pathogenesis of tropical pulmonary eosinophilia (TPE), we analyzed genetic polymorphisms of both in 181 individuals from southern India with varying clinical manifestations of Wuchereria bancrofti infection (including 26 with TPE). Using haplotype frequency analysis, we identified four known (of nine) and two novel haplotypes for EDN (1, 2, 7, 8, 10, and 11). For ECP, five (of seven known) haplotypes (1-5) were identified. Although we found no significant association between frequencies of EDN and ECP polymorphisms and TPE development, we observed a unique pattern of EDN and ECP polymorphism distribution among this population. Genotype TT at locus 1088 of ECP in one TPE patient was not observed in any other clinical group. Although the EDN and ECP polymorphisms appear unlikely to be associated with the development of TPE, further analyses will be more definitive.

Case report and brief commentary: Wuchereria bancrofti and Onchocerca volvulus co-infection in a refugee from Sierra Leone

Filarial infection is endemic in the tropics and is a public health problem in Africa, Asia, South and Central America, and the Pacific Islands. Co-infection with filarial nematodes, if unrecognized, can result in untoward therapeutic consequences. We report a case of co-infection of Wuchereria bancrofti and Onchocerca volvulus that was diagnosed by direct blood smear (W. bancrofti ) and serology (O. volvulus) in a native of Sierra Leone. We comment briefly on the therapeutic implications of the co-infection.

Malaria-filaria coinfection in mice makes malarial disease more severe unless filarial infection achieves patency

Coinfections are common in natural populations, and the literature suggests that helminth coinfection readily affects how the immune system manages malaria. For example, type 1-dependent control of malaria parasitemia might be impaired by the type 2 milieu of preexisting helminth infection. Alternatively, immunomodulatory effects of helminths might affect the likelihood of malarial immunopathology. Using rodent models of lymphatic filariasis (Litomosoides sigmodontis) and noncerebral malaria (clone AS Plasmodium chabaudi chabaudi), we quantified disease severity, parasitemia, and polyclonal splenic immune responses in BALB/c mice. We found that coinfected mice, particularly those that did not have microfilaremia (Mf(-)), had more severe anemia and loss of body mass than did mice with malaria alone. Even when controlling for parasitemia, malaria was most severe in Mf(-) coinfected mice, and this was associated with increased interferon- gamma responsiveness. Thus, in Mf(-) mice, filariasis upset a delicate immunological balance in malaria infection and exacerbated malaria-induced immunopathology.

Tropical pulmonary eosinophilia: a case series in a setting of nonendemicity

BACKGROUND

Tropical pulmonary eosinophilia (TPE) is a rare but serious manifestation of infection with the lymphatic filarial parasites Wuchereria bancrofti and Brugia malayi. Although endemicity is limited to the tropical and subtropical regions of Africa, South America, and Asia, immigration and travel practices have led to the diagnosis of TPE in areas of nonendemicity.

METHODS

We herein present a case series of all patients with TPE who presented to the Toronto General Hospital during 1990-2003.

RESULTS

Seventeen individuals presented with TPE during the study period, and all were of South Asian ancestry. All 17 received an incorrect diagnosis at presentation (median number of consultations before diagnosis, 2), the most frequent of which was asthma (76%). Eosinophil count, serum immunoglobulin E levels, and anti-filarial antibody titers were elevated in all patients. Ten of 14 patients had an abnormal chest radiograph finding, and 11 of 12 patients had abnormal results of pulmonary function tests.

CONCLUSIONS

TPE is an important diagnostic consideration in patients with eosinophilia, respiratory symptoms, and history of exposure to this disease. In the untreated individual, TPE can lead to chronic and progressive respiratory compromise and death. Prompt recognition and treatment with diethylcarbamazine is therefore key to minimizing morbidity and mortality.

Filarial chyluria: Long-term experience of a university hospital in India

BACKGROUND

Filariasis is an endemic problem in various Indian states. We evaluated the results of long-term follow up (10-20 years) of patients with filarial chyluria.

METHODS

We conducted a retrospective analysis of 160 patients treated for filarial chyluria who presented to the Banaras Hindu University Hospital from 1982 to 1992. Eighty-four patients (52.5%) were treated using diethylcarbamazine (DEC) and a fat restricted diet and 76 patients (47.5%) underwent surgery. To examine the long-term effects of filarial chyluria we analysed data on post-treatment recurrence, weight gain, dietary freedom, chyluria free period and a number of other associated factors.

RESULTS

Previous history of filariasis or its complication was documented in 19% of patients. In 71% of cases, cystoscopy showed that chylous efflux was predominant in the left ureteric orifice. The long-term remission rate was 62% in the conservatively managed group (DEC + fat restricted diet), whereas 90% of patients in the operated group were cured. Postoperative recurrence rate was 10%. There was more weight gain and dietary freedom along with a longer chyluria free period in the operated group relative to the conservatively managed group.

CONCLUSIONS

Definitive surgical ablation of lymphatic urinary fistula is better than conservative medical management because it has a higher success rate, more dietary freedom and, therefore, better patient acceptability.