Hospital-based surveillance for HTLV-1/2 infections in Spain

Hospital admissions in individuals with HTLV-1 infection in Spain

OBJECTIVE

To examine the clinical burden and disease spectrum, as well as time trends for human T-cell leukemia virus type 1 (HTLV-1) and HTLV type 2 (HTLV-2) hospital admissions.

DESIGN

Retrospective, observational study using the Spanish National Hospital Discharge Database.

METHODS

Information for the diagnostic codes HTLV-1 and HTLV-2 using the International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) was retrieved from the national public registry since 1997--2015.

RESULTS

From a total of 66 462 136 nationwide hospital admissions recorded during the study period, 135 included HTLV diagnosis, being HTLV-1 in 115 (85.2%) and HTLV-2 in 20 (14.8%). The overall hospital admission rate because of HTLV was 2.03 per million, without significant yearly changes. First admissions represented 104 (77%) whereas 31 (23%) were re-admissions. The median in-hospital stay for HTLV patients was 9 days. In-hospital death occurred in 11 (8.1%). The median age of individuals with HTLV admission was 48 years and 60 (44.4%) were women. HTLV was recorded as the main diagnosis in 20%. The most frequent clinical conditions recorded alongside HTLV diagnosis were myelopathy (61; 45.2%), leukemia/lymphoma (30; 22.2%), solid organ transplantation (14; 10.4%) and child delivery (7; 5.2%).

CONCLUSION

The rate of HTLV diagnosis in hospitalized patients in Spain is low, roughly of two per million admissions. Despite continuous large immigrant flows from HTLV-1 endemic areas, no significant rising in hospitalizations because of HTLV-1 associated illnesses were noticed during the last two decades. Classical clinical complications of HTLV-1 infection, such as myelopathy and lymphoma account for more than two-thirds of cases.

Molecular epidemiology and clinical features of human T cell lymphotropic virus type 1 infection in Spain

Human T cell lymphotropic virus type 1 (HTLV-1) infection in Spain is rare and mainly affects immigrants from endemic regions and native Spaniards with a prior history of sexual intercourse with persons from endemic countries. Herein, we report the main clinical and virological features of cases reported in Spain. All individuals with HTLV-1 infection recorded at the national registry since 1989 were examined. Phylogenetic analysis was performed based on the long terminal repeat (LTR) region. A total of 229 HTLV-1 cases had been reported up to December 2012. The mean age was 41 years old and 61% were female. Their country of origin was Latin America in 59%, Africa in 15%, and Spain in 20%. Transmission had occurred following sexual contact in 41%, parenteral exposure in 12%, and vertically in 9%. HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP) was diagnosed in 27 cases and adult T cell leukemia/lymphoma (ATLL) in 17 subjects. HTLV-1 subtype could be obtained for 45 patients; all but one belonged to the Cosmopolitan subtype a. One Nigerian pregnant woman harbored HTLV-1 subtype b. Within the Cosmopolitan subtype a, two individuals (from Bolivia and Peru, respectively) belonged to the Japanese subgroup B, another two (from Senegal and Mauritania) to the North African subgroup D, and 39 to the Transcontinental subgroup A. Of note, one divergent HTLV-1 strain from an Ethiopian branched off from all five known Cosmopolitan subtype 1a subgroups. Divergent HTLV-1 strains have been introduced and currently circulate in Spain. The relatively large proportion of symptomatic cases (19%) suggests that HTLV-1 infection is underdiagnosed in Spain.

Trends in the prevalence and distribution of HTLV-1 and HTLV-2 infections in Spain

Background

Although most HTLV infections in Spain have been found in native intravenous drug users carrying HTLV-2, the large immigration flows from Latin America and Sub-Saharan Africa in recent years may have changed the prevalence and distribution of HTLV-1 and HTLV-2 infections, and hypothetically open the opportunity for introducing HTLV-3 or HTLV-4 in Spain. To assess the current seroprevalence of HTLV infection in Spain a national multicenter, cross-sectional, study was conducted in June 2009.

Results

A total of 6,460 consecutive outpatients attending 16 hospitals were examined. Overall, 12% were immigrants, and their main origin was Latin America (4.9%), Africa (3.6%) and other European countries (2.8%). Nine individuals were seroreactive for HTLV antibodies (overall prevalence, 0.14%). Evidence of HTLV-1 infection was confirmed by Western blot in 4 subjects (prevalence 0.06%) while HTLV-2 infection was found in 5 (prevalence 0.08%). Infection with HTLV types 1, 2, 3 and 4 was discarded by Western blot and specific PCR assays in another two specimens initially reactive in the enzyme immunoassay. All but one HTLV-1 cases were Latin-Americans while all persons with HTLV-2 infection were native Spaniards.

Conclusions

The overall prevalence of HTLV infections in Spain remains low, with no evidence of HTLV-3 or HTLV-4 infections so far.

[Intermediate uveitis due to human T-cell lymphotropic virus type 1]

CASE REPORT

The case of a 66-year-old woman with intermediate uveitis in both eyes and progressive weakness of lower limbs is reported. A human T-lymphotropic virus type 1 (HTLV-1) infection was detected in the serological study, with the patient being diagnosed with tropical spastic paraparesis and HTLV-1 intermediate uveitis. The patient made good progress with oral steroid treatment.

DISCUSSION

The clinical and epidemiological aspects of HTLV-1 infection are discussed. We recommend a serological determination of the virus in intermediate uveitis of unknown origin in people from endemic areas or with neurological symptoms.

Prevalence of HTLV-1/2 infections in Spain: A cross-sectional hospital-based survey

The presence of antibodies to human T-lymphotropic virus (HTLV) types 1 and 2 was examined in 5742 sera belonging to consecutive adult outpatients attended during June 2008 at 13 different hospitals across Spain. Overall, 58.8% were female. Foreigners represented 8% of the study population. Seven individuals were seropositive for HTLV-2 (overall prevalence 0.12%). No cases of HTLV-1 infection were found. All HTLV-2(+) subjects were Spanish natives, of whom six were coinfected with HIV-1 and five with hepatitis C virus (HCV). Moreover, all but one of the HTLV-2(+) subjects had been intravenous drug users. In summary, this cross-sectional survey suggests that the rate of HTLV infection in Spain is low, and is mostly represented by HTLV-2. Infected individuals are generally Spanish natives with a prior history of intravenous drug use and are coinfected with HIV-1 and/or HCV.