IgG antibody responses in early experimental sparganosis and IgG subclass responses in human sparganosis

Antigenic components in the crude extracts of Spirometra mansoni plerocercoid were analyzed in early experimental infections and in IgG subclass observed in clinical sparganosis. By IgG immunoblot, sera obtained serially from experimental mice, fed 5 spargana each, were reacted with the crude extracts. Protein bands at 36-26 kDa and 103 kDa showed positive reactions since two weeks after infection. In a differential immunoblot, in which a monospecific antibody against sparganum chymase at 36 kDa was pre-treated, the reactions at 36-26 kDa disappeared, indicating that the sparganum chymase and its degradation products invoked IgG antibody reactions. When 69 patients sera of human sparganosis were examined for their IgG subclass responses, IgG4 levels showed the highest reaction which was followed by IgG1. The IgG4 antibody also reacted mainly with 36-31 kDa protease. These results indicate that 36 kDa chymase of S. mansoni plerocercoid is the main antigenic component inducing IgG antibody response in early stage of experimental sparganosis and for specific IgG subclass reactions in human sparganosis.     

Human proliferative sparganosis update

Proliferative sparganosis is one of the most bizarre and mysterious parasitic diseases ever described. The causative parasite is Sparganum proliferum, which is a pseudophyllidean cestode distinct from Spirometra tapeworms. Here we overview this rare but fascinating disease with the all original case reports on human patients published in the last 115 years.Proliferative sparganosis is clearly divided into two disease types, cutaneous and internal proliferative sparganosis. Cutaneous type starts with a skin eruption caused by the dermal invasion of a sparganum. Skin lesion progresses to larger areas of the body if left untreated. Various internal organs and body wall can be eventually affected. The clinical symptoms of patients in this group are very similar to each other. Molecular data suggest that cutaneous proliferative sparganosis is caused by S. proliferum of which genetic variation is limited, regardless of the time or localities of the emergence of patients.Internal proliferative sparganosis, on the other hand, is much more heterogeneous. Some cases show aggressive infection in internal organs, while others show only restricted lesions. Some of the cases that had been cited as proliferative sparganosis in the past literature were removed from the list, because they were judged as cyclophyllidean tapeworm infections. DNA sequencing is mandatory for the definite diagnosis of proliferative sparganosis.The Venezuelan strain of S. proliferum is maintained in experimental mice in Japan, which is fully prepared for the experimental study with advanced technologies in modern molecular biology.     

A case of breast sparganosis

A 29-year-old Korean woman visited the Department of Surgery in MizMedi Hospital with a palpable itching mass on the right breast that had existed for the past 7 months. She had no history to eat either frogs or snakes, but had the history of drinking impure water. Sonography revealed a serpiginous hypoechoic tubular structure associated with partial fat necrosis in breast parenchymal layer and subcutaneous fat layer. It also revealed oval cystic lesions. At operation, an ivory white opaque ribbon-like worm that measured 16.5 cm in length and 0.5 cm in width was extracted. Anti-sparganum specific serum IgG level in the patient's serum (absorbance = 0.71), measured by ELISA, was found to be significantly higher than those of normal controls (cut off point = 0.21). Sonography and ELISA appear to be helpful to diagnose sparganosis. Breast sparganosis is rarely found throughout the world.     

A case of sparganosis in the leg

The life-span of the sparganum in humans is not exactly known, but it may survive longer than 5 years in some patients. We experienced a case infected with a sparganum that is presumed to have lived for 20 years in a patient's leg. The patient was a 60-year-old woman, and she was admitted to a hospital due to ankle pain that was aggravated on dorsiflexion. She had noticed a mass on her knee some 20 years ago, but she received no medical management for it. The mass moved into the ankle joint 3 months before the current admission, and then the aforementioned symptoms appeared. A living sparganum was recovered by surgery, and the calcified tract near the knee was proved to be the pathway along which the larva had passed.     

A seroepidemiologic survey for human sparganosis in Gangweon-do

Gangweon-do is known to be highly endemic area of sparganosis more than other provinces in Korea. A seroepidmiologic examination for the detection of anti-Spirometra erinacei plerocercoid IgG in serum was carried out in normal inhabitants in Hongcheon-gun, Gangweon-do. Sere were tested by enzyme-linked immunosrobent assay (ELISA) for the anti-sparganum antibodies. Positive rate for anti-sparganum antibody in 719 adults was 3.3%. Data of the questionnaire for 24 ELISA positive inhabitants revealed that 20 had a history of eating raw meat of snakes, 24 had a history of eating frogs, and 24 had a history of drinking stream water. Two positive cases had a past history of sparganosis. Two positive cases showed current symptoms of sparganosis. The data revealed that ELISA would be useful to find infected cases among normal inhabitants at sparganosis-endemic areas.     

Feminization and reduction of testicular weight in mouse sparganosis

After infection of male mice with the plerocercoids (spargana) of Spirometra mansoni, serum levels of estrogen and testicular weight were analyzed by enzyme-linked immunosorbent assay (ELISA) and weighing machine, respectively. The serum level of estrogen increased progressively in infected mice compared with normal controls, whereas the testicular weight of infected mice decreased significantly (P < 0.05). These results suggest that certain substances from spargana change the steroid hormone metabolisms in the host by unknown pathways, and chronic infection may contribute to change of the function of steroid hormone target organ, i.e., testis, in male mice.     

Changes of serum adiponectin levels in murine experimental sparganosis

The weight gain phenomenon associated with sparganosis has been well documented and was first recognized in the 1960s. Many studies have been conducted regarding the plerocercoid growth factor in the larva of Spirometra mansoni. In the present study, we hypothesized that the weight gain may be affected by the adipocyte secreted hormones, i.e., adiponectin, which is secreted from the adipose tissues in case of tissue migrating parasitic infections. Specifically, we attempted to ascertain whether the serum levels of adiponectin change in murine sparganosis. However, serum adiponectin levels assayed by ELISA evidenced no significant changes after an experimental infection (P > 0.05). Finally, the weight gain phenomenon in mouse sparganosis is not associated with changes in adiponectin levels, and further investigations involving parasitic infection-induced weight gain remain necessary.     

A case of sparganosis mimicking a varicose vein

Recent advances in radiological and serological techniques have enabled easier preoperative diagnosis of sparganosis. However, due to scarcity of cases, sparganosis has been often regarded as a disease of other etiologic origin unless the parasite is confirmed in the lesion. We experienced a case of sparganosis mimicking a varicose vein in terms of clinical manifestations and radiological findings. Sparganosis should be included among the list of differential diagnosis with the varicose vein.     

Imported submicroscopic malaria in Madrid

ABSTRACT: BACKGROUND: Submicroscopic malaria (SMM) can be defined as low-density infections of Plasmodium that are unlikely to be detected by conventional microscopy. Such submicroscopic infections only occasionally cause acute disease, but they are capable of infecting mosquitoes and contributing to transmission. This entity is frequent in endemic countries; however, little is known about imported SMM. The goals of this study were two-fold: a) to know the frequency of imported SMM, and b) to describe epidemiological, laboratorial and clinical features of imported SMM. METHODS: A retrospective study based on review of medical records was performed. The study population consisted of patients older than 15 years attended at the Tropical Medicine Unit of Hospital Carlos III, between January 1, 2002 and December 31, 2007. Routinely detection techniques for Plasmodium included Field staining and microscopic examination through thick and thin blood smear. A semi-nested multiplex malaria PCR was used to diagnose or to confirm cases with low parasitaemia. RESULTS: SMM was diagnosed in 104 cases, representing 35.5% of all malaria cases. Mean age (IC95%) was 40.38 years (37.41-43.34), and sex distribution was similar. Most cases were in immigrants, but some cases were found in travellers. Equatorial Guinea was the main country where infection was acquired (81.7%). Symptoms were present only in 28.8% of all SMM cases, mainly asthenia (73.3% of symptomatic patients), fever (60%) and arthromialgias (53.3%). The associated laboratory abnormalities were anaemia (27.9%), leukopaenia (15.4%) and thrombopaenia (15.4%). Co-morbidity was described in 75 cases (72.1%). CONCLUSIONS: Results from this study suggest that imported SMM should be considered in some patients attended at Tropical Medicine Units. Although it is usually asymptomatic, it may be responsible of fever, or laboratory abnormalities in patients coming from endemic areas. The possibility of transmission in SMM has been previously described in endemic zones, and presence of vector in Europe has also been reported. Implementation of molecular tests in all asymptomatic individuals coming from endemic area is not economically feasible. So reemergence of malaria (Plasmodium vivax) in Europe may be speculated.     

The changes of histopathology and serum anti-sparganum IgG in experimental sparganosis of mice

The present study is intended to observe the chronologic changes of experimental sparganosis by histopathological observation and detection of circulating anti-sparganum IgG antibody using ELISA. Each of 25 mice was infected with five spargana, and they were examined after 1, 2, 4, 10 weeks or 6 months from infection. The followings are summarized results. 1. The plerocercoids were detected in the subcutaneous tissue of the trunk, neck or axilla, but a few often extended into the skeletal muscle. The recovery rates were 72% at the first week, 80% at the second week, 95% at the fourth week, 92% at the tenth week and 100% at the sixth month. The larvae grew slowly in both length and weight until 6 months. 2. Histopathologically, most of the larvae were observed alive in the soft tissue or skeletal muscle. Numerous eosinophils, neutrophils, lymphocytes and plasma cells were infiltrated focally around the worms by the second week, but they surrounded the worms to form a layer of inflammatory reaction after 4 weeks of infection. Also histiocytes and fibroblasts began to appear around the inflammatory cells at 4 weeks. After 10 weeks, the worms encircled by a thin fibrous layer were found. After 6 months, the worms were surrounded by either fibrous tissue or active inflammatory cells. The inflammation looked more severe in the tracks left by the worms, rather than around the worms. 3. The level of anti-sparganum IgG antibody in the serum showed an increase by the fourth week, and a rapid and continuous increase was observed thereafter by the tenth week after infection.(ABSTRACT TRUNCATED AT 250 WORDS)