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uk patients with vl are often referred to the hospital for tropical diseases , london , for confirmation of diagnosis or treatment .
thirty - nine patients were identified from our hospital database and laboratory records , representing 83% of cases reported in the united kingdom ( figure 1 ) .
number of visceral leishmaniasis ( vl ) cases , united kingdom , 1985 - 2004 ( data from health protection agency).(data from health protection agency ) .
the mean age of these patients was 36 years ( range 266 years ) ; 4 patients were < 15 years of age .
patients acquired visceral leishmaniasis while in the following areas : 30 ( 76.9% ) in mediterranean countries ( 13 in spain , 9 in italy , 4 in greece , 3 in malta , 1 in cyprus ) , 5 ( 12.8% ) from africa , 3 ( 7.7% ) from asia , and 1 ( 2.6% ) from south america . during the entire 20-year period ,
55.5% of patients had been tourists to these vl - endemic regions , and 44.5% were immigrants or refugees , but after 2000 , all patients were tourists .
two patients had significant immunosuppression from other causes : 1 from chronic lymphatic leukemia and 1 from immunosuppressive drugs received after kidney transplantation .
time from onset of symptoms to diagnosis was 111 months ( mean 3 months ) .
diagnoses of vl were confirmed by > 1 method : microscopic identification of amastigotes in tissue aspirates ; histologic examination of biopsy material from bone marrow , liver , or spleen ; serologic analysis ; and pcr for leishmania dna ( 7 ) .
leishmania amastigotes were found in 32 bone marrow aspirates , 3 liver biopsy specimens , 2 splenic aspirates , and 1 skin biopsy specimen .
pcr to detect leishmania dna has been performed in this study since 1995 and was positive in 7 of 11 cases .
it was the method of confirmatory diagnosis for 1 patient ( performed on a bone marrow aspirate that had no visible amastigotes ) .
serum analysis for leishmania antibodies was performed on samples from 33 patients ; results were positive for all hiv - negative patients and for 2 of 13 hiv - positive patients ( table 1 ) .
* vl , visceral leishmaniasis ; ifat , indirect immunofluorescent antibody test , 19851994 ; dat , direct antibody agglutination test ( beginning in 1989 ) ; latex , latex agglutination test , 19962003 ; k39 , recombinant k39 antigen detection test ( beginning in 2002 ) ; + , positive result ;  , negative result .
before 1995 , treatment of leishmaniasis involved several drugs , including sodium stibogluconate , paromomycin , meglumine antimoniate , and pentamidine .
the latter 2 were used for patients who received initial treatment outside the united kingdom ; within the united kingdom , most ( 59% ) patients were treated with sodium stibogluconate .
after 1995 , liposomal amphotericin became the drug of choice and was used in 14 ( 83% ) of 17 patients .
of the 13 patients who had a relapse , 8 ( 53% ) had hiv coinfection .
of the 13 who had hiv coinfection , 8 ( 62% ) had a relapse , compared with 7 ( 27% ) of the 26 hiv - negative patients who had a relapse .
two patients had other risk factors for relapse : 1 had had a kidney transplant , and the other had chronic active hepatitis b. three patients who had relapses had no apparent risk factors .
relapse occurred in 5 ( 33% ) of 15 patients who received sodium stibogluconate , compared with 1 ( 7% ) of 14 who received liposomal amphotericin as their initial drug . at first , relapsed patients were treated with a combination of sodium stibogluconate and allopurinol , which was unsuccessful in contrast with its reported success in kenya , or with amphotericin deoxycholate ( 8) .
hiv - infected patients who had relapses received further treatment with liposomal amphotericin , usually successful , but 2 became unresponsive to treatment .
miltefosine was used in 2 patients with hiv coinfection who had relapses , but relapses recurred , 1 while the patient was still receiving the drug ( 9 ) . since 2000 , pentamidine prophylaxis has been used in 3 immunocompromised patients .
na stibo , stibogluconate ; meg , meglumine antimoniate ; paro , paromomycin ; pent , pentamidine ; amb , ambisome ; amp , amphotericin .
the number of patients in the final cure category excludes patients who had had a relapse .
the 3 patients who died had advanced hiv disease ; 1 had an additional complication of liver failure secondary to hepatitis c cirrhosis .
the data from this cohort show that vl is imported into the united kingdom at a constant rate , particularly in adult male tourists to the mediterranean , and that during the past 20 years , hiv and vl had interacted strikingly .
the mediterranean vl - endemic zone accounts for only a small proportion of vl cases globally , but it is a popular holiday destination for the british , and tourism is driving the epidemiology of the imported infection . in the past 5 years , we have seen no immigrants or refugees with vl .
the data show that high rates of tourism to an area of low endemicity for a parasitic disease can result in a substantial number of imported cases .
the highest rates of reported hiv coinfection worldwide are from europe , where 85% of the cases are from the southwest ; 71% of these are in intravenous drug users ( 2 ) .
hiv / vl coinfection is a serious disease that has high death rates , reflected by the 3 deaths in our cohort .
highly active antiretroviral therapy for hiv is decreasing the numbers of these coinfections and improving survival rates ( 10,11 ) .
this delay resulted mainly from physicians failure to consider the diagnosis , although a few cases were difficult to diagnose . for
2 patients , initial microscopic examination of bone marrow biopsy results did not show amastigotes ; reinspection showed scarce amastigotes .
for another patient , serologic results by direct agglutination were negative when performed early in the course of disease but positive when repeated .
the low sensitivity of serologic tests for hiv - infected patients in this cohort confirms that serologic tests can not be relied on as a means of excluding vl in hiv - infected patients .
our cohort shows a rise and fall in the proportion of cases of hiv / vl coinfection , starting in the early 1990s , rising to a peak of 50% during 19931996 , and then decreasing , possibly because of greater use of highly active antiretroviral therapy .
vl remains an imported disease in the united kingdom and is often associated with hiv infection .
we suggest that a formal notification system for visceral leishmaniasis in the united kingdom , as elsewhere in europe , would be beneficial for monitoring trends and health planning ( 12 ) .
our data also show the importance of looking at rare imported diseases over a long period so that emerging risk factors can be identified .
these data also highlight the usefulness of having 1 center that deals with unusual infections , where expertise in diagnosis and management can be built up and maintained .
a 20-year ( 19852004 ) retrospective review of 39 patients with imported visceral leishmaniasis found that tourism to mediterranean countries and hiv infection were associated with visceral leishmaniasis . 
 diagnosis was often delayed . 
 treatment with liposomal amphotericin b has improved prognosis . 
 visceral leishmaniasis should be made a reportable disease .