Visceral larva migrans in immigrants from latin america

To determine whether increased migration is associated with an increase in incidence of toxocariasis (visceral larva migrans), we analyzed clinical data obtained from immigrants from Latin America. Although infection with Toxocara sp. roundworm larvae is distributed worldwide, seroprevalence is highest in tropical and subtropical areas.

In vitro selection of variants resistant to beta-lactams plus beta-lactamase inhibitors in CTX-M beta-lactamases: predicting the in vivo scenario?

CTX-M β-lactamases are the most prevalent group of enzymes within the extended-spectrum β-lactamases (ESBL). The therapeutic options for CTX-M-carrying isolates are scarce, forcing the reexamination of the therapeutic possibilities of β-lactams plus β-lactamase inhibitors (BBLIs). Inhibitor-resistant CTX-M β-lactamases (IR-CTX-M) have not hitherto been described in natural isolates. In this study, 168 cultures of the hypermutagenic Escherichia coli GB20 strain carrying plasmid pBGS18 with different bla(CTX-M) genes were submitted to parallel experimental evolution assays in the presence of increasing concentrations of a combination of amoxicillin and clavulanate. Fourteen CTX-M β-lactamases belonging to the three most representative clusters (CTX-M-1, -2, and -9) and the two main phenotypes (cefotaxime resistance and cefotaxime-ceftazidime resistance) were studied. Three types of IR-CTX-M mutants were detected, having mutations S130G, K234R, and S237G, which are associated with different resistance patterns. The most frequently recovered mutation was S130G, which conferred the highest resistance levels to BBLIs (reaching 12 μg/ml for amoxicillin-clavulanate and 96 μg/ml for piperacillin-tazobactam when acquired by CTX-M-1 cluster enzymes). The S130G change also provided a clear antagonistic pleiotropy effect, strongly decreasing the enzyme's activity against all cephalosporins tested. A double mutation, S130G L169S, partially restored the resistance against cephalosporins. A complex pattern observed in CTX-M-58, carrying P167S and S130G or K234R changes, conferred ESBL and IR phenotypes simultaneously. The K234R and S237G changes had a smaller effect in providing inhibitor resistance. In summary, IR-CTX-M enzymes might evolve under exposure to BBLIs, and the probability is higher for enzymes belonging to the CTX-M-1 cluster. However, this process could be delayed by antagonistic pleiotropy.

Utility of Schistosoma bovis adult worm antigens for diagnosis of human schistosomiasis by enzyme-linked immunosorbent assay and electroimmunotransfer blot techniques

Immunodiagnostic methods based on the detection of antibodies continue to be the most effective and practical methods for the diagnosis of imported schistosomiasis. Schistosoma bovis is a species whose final natural hosts are bovines, ovines, caprines, and small wild ruminants. Different studies have demonstrated the analogies existing between S. bovis and other Schistosoma species which affect humans. The objective of this work was to evaluate the utility of S. bovis adult worm antigens (AWA) for the diagnosis of imported human schistosomiasis by enzyme-linked immunosorbent assay (ELISA) and electroimmunotransfer blotting (EITB) techniques. By detecting eggs, the ELISA for S. bovis AWA was able to definitively detect imported cases with a sensitivity of 94%. The specificity of the ELISA for S. bovis AWA was 97%. There were no differences between the results of the S. bovis AWA ELISA for patients infected with Schistosoma mansoni and those infected with Schistosoma haematobium. The EITB technique showed bands of 85, 37, and 20 kDa, which are characteristic of infections with Schistosoma spp. Specific bands to indicate infection by different species of Schistosoma have not been detected. The combined use of the ELISA for S. bovis AWA and EITB increased the global sensitivity of the study to 97%. Our findings suggest that the ELISA for S. bovis AWA is a useful test for the immunodiagnosis of imported schistosomiasis and that EITB for detecting S. bovis AWA permits the confirmation of diagnosis when the ELISA for S. bovis AWA is positive.

Infectious diseases in immigrants from the perspective of a tropical medicine referral unit

Immigrants from less developed countries to Europe are growing in number and could contribute to the emergence of some infectious diseases. To address this issue, we conducted a descriptive study of 988 immigrants, of whom 79.9% were sub-Saharan Africans and 72% were of undocumented origin. Fever, pruritus, eosinophilia, visceromegaly, and anemia were more frequent in Africans, while a cough was more common Latin Americans (P < 0.005). The most frequent diagnoses were previous hepatitis B (46.5%), latent tuberculosis (44.2%), filariasis (24.8%), infection with intestinal helminths (15.4%), malaria (15.1%), infection with intestinal protozoa (10%), hepatitis C (8.8%), other non-parasitic infections (7.8%), active hepatitis B (7.6%), sexually transmitted diseases (7.5%), active tuberculosis (5.8%), and infection with human immunodeficiency virus (HIV) (5.2%). Past and active hepatitis B and C, active tuberculosis, infection with HIV, malaria, and filariasis were more frequent in Africans (P < 0.005). Thirty-two other tropical diseases were also diagnosed.

Microsporidiosis in travelers with diarrhea from the tropics

BACKGROUND

Microsporidia are protozoa which mainly affect severely immunodepressed AIDS patients in developed countries as well as those in developing ones. Traveler's diarrhea affects approximately 40% of people traveling from industrialized countries to developing ones, and no pathogens are identified in many of those patients on their returning, suggesting that known enteropathogens escape detection or entirely new ones could be responsible. Very few reports of travel-related microsporidiosis have been described.

METHODS

Between January, 1996 and January, 1998, a total of 40 European travelers from the tropics with a clinical picture of protected diarrhea (three or more loose stools per day lasting for more than 3 weeks) were evaluated. Weber's trichrome modified by Kokoskin stain for microsporidial spores were performed in stool samples of every patient. Microsporidial DNA extraction and PCR amplification were attempted in every stool sample where microsporidial spores were observed.

RESULTS

Four cases of imported Enterocytozoon bieneusi were detected: one HIV-infected short term traveler, a pregnant long term traveler, and two immunocompetent short term travelers. Diarrhea was self-limited, and the spores cleared from the stools in all HIV-non infected travelers, but showed a chronic course in the HIV-infected one.

CONCLUSIONS

Available data is too limited to affirm that residence or travel in tropical countries increases the risk for microsporidial infection, but the cases presented here suggest that E. bieneusi could be a cause of self-limited diarrhea in immunocompetent travelers returning from the tropics or could chronically affect immunocompromised HIV-infected travelers.

Clinicoepidemiological study of imported malaria in travelers and immigrants to Madrid

BACKGROUND

The number of Spanish travelers visiting malaria endemic areas, and the number of immigrants from malarial countries arriving in Spain are continuously increasing. However, little information about imported cases in Spain is available.

METHODS

A prospective clinicoepidemiological study of imported cases of malaria diagnosed at a referral teaching hospital in Madrid, Spain.

RESULTS

Of the 160 patients, sixty (37.5%) were immigrants and 100 (62.5%) Spanish nationals. Malaria was acquired in Africa by 98.3% of immigrants and in 83.0% of travelers. Falciparum malaria accounted for 71.8% of the cases, P. vivax for 11.9%, P. ovale for 10.6% and P. malarie for 5. 0%. Eleven (6.9%) patients, all immigrants, were asymptomatic. Severe complications were recorded in 17 (10.6%): 7, severe anemia; 3, cerebral malaria; 2, renal failure; 1, spontaneous splenic rupture; 1, acute pulmonary edema; 1, sepsis; 1, acute cerebrovascular accident; and 1, disseminated intravascular coagulation. There were no fatal cases. Among the 100 Spanish nationals, 44% did not follow any prophylaxis, 29% followed a correct prophylaxis, 27% were considered defaulters, and 39% took self-treatment without cure.

CONCLUSIONS

There is a changing pattern of imported malaria in Madrid, with one third occurring in immigrants and two thirds in nationals. This data provides information about the reemergence of imported malaria to Europe.

[2 cases of toxocariasis (visceral larva migrans)]

BACKGROUND

Different epidemiological studies have demonstrated that specific anti-Toxocara antibodies are detected in the serum of a high percentage of the Spanish population. But very few clinical cases of visceral larva migrans are being confirmed.

METHODS AND RESULTS

Two cases of visceral toxocarosis, in two sisters, are described. In the first, the prevailing clinic was swelling of joints and upper respiratory tract symptoms; and asthma and cutaneous allergic manifestations in the second patient. Both cases presented with an elevated blood eosinophil count, high levels of total IgE and high titlers of anti-Toxocara antibodies. All symptoms disappeared after treatment with diethylcarbamazine and they remain asymptomatic several months after.

CONCLUSIONS

In pediatric population, toxocarosis should be ruled out in every patient with respiratory symptoms, allergic cutaneous manifestations and elevated blood eosinophil count. The anti-Toxocara antibodies assay is of great value in establishing the diagnosis of this parasitic disease.