Leprosy in Refugees and Migrants in Italy and a Literature Review of Cases Reported in Europe between 2009 and 2018

Leprosy is a chronic neglected infectious disease that affects over 200,000 people each year and causes disabilities in more than four million people in Asia, Africa, and Latin America. The disease can appear with a wide spectrum of clinical forms, and therefore the clinical suspicion is often difficult. Refugees and migrants from endemic countries affected by leprosy can remain undiagnosed in Europe due to the unpreparedness of clinicians. We retrospectively describe the characteristics of 55 refugees/migrants with a diagnosis of leprosy established in Italy from 2009 to 2018. Continents of origin were Africa (42%), Asia (40%), and South and Central America (18%). The symptoms reported were skin lesions (91%), neuropathy (71%), edema (7%), eye involvement (6%), fever (6%), arthritis (4%), and lymphadenopathy (4%). Seven patients (13%) had irreversible complications. Overall, 35% were relapses and 66% multibacillary leprosy. Furthermore, we conducted a review of 17 case reports or case series and five nationwide reports, published in the same decade, describing 280 migrant patients with leprosy in Europe. In Europe, leprosy is a rare chronic infectious disease, but it has not completely disappeared. Diagnosis and treatment of leprosy in refugees and migrants from endemic countries are a challenge. European guidelines for this neglected disease in this high-risk population would be beneficial.


Study Population and Data Collection
The Dermatological Clinic, National Reference Center for Hansen's Disease, Ospedale Policlinico San Martino, Sistema Sanitario Regione Liguria, Istituto di Ricovero e Cura a Carattere Scientifico per l'Oncologia, Genoa has observed more than 90% of leprosy cases in Italy since 1999. The Department of Infectious, Tropical Diseases, and Microbiology (DITM), Istituto di Ricovero e Cura a Carattere Scientifico Sacro Cuore Don Calabria Hospital of Negrar di Valpolicella (Verona) is a National Referral Center for Neglected Tropical and Parasitic Diseases and for cases of patients with rare infectious diseases in the Veneto Region. The analysis of the population followed by these two centers is therefore representative of the population of leprosy in migrants present in Italy.
We retrospectively collected data from the medical records of refugees/migrants with a diagnosis of leprosy admitted to the two centers between January 2009 and December 2018.
The following information were recorded in the study case report form (1) demographic characteristics of the patients (country of origin, gender and age); (2) duration of stay in Europe; (3) previous diagnosis and treatment of leprosy; (4) time elapsed from symptom onset to diagnosis; (5) clinical manifestations; (6) diagnostic methods used; (7) WHO classification [19]; (8) Ridley-Jopling classification [20]; (9) treatment (type and duration); and (10) outcome. Data were entered into a pre-designed Excel file and analyzed.

Review: Search Strategy and Selection Criteria
We conducted a review of case reports and case series published between 2009 and 2018. No language restrictions were applied. Inclusion criteria were all case reports or case series reporting imported cases of leprosy diagnosed in Europe, upon the availability of main demographic and epidemiologic characteristics. Exclusion criteria were European patients. The following databases were searched for relevant studies: MEDLINE (PubMed), EMBASE (Embase.com), CENTRAL (Cochrane Library), Latin American and Caribbean Health Science Information Database (LILACS) (Bireme), and ClinicalTrials.gov (www.clinicaltrials.gov). The detailed electronic search strategy is reported in Appendix A. Figure 1 summarizes the search strategy as well as the references identified through other sources.

Definitions
The diagnosis of leprosy is made in the presence of one or more of the following criteria [4,19]: -Clinical: definite loss of sensation in a pale (hypopigmented) or reddish skin patch (SP) or a thickened or enlarged peripheral nerve with loss of sensation and/or weakness of the muscles supplied by that nerve. -Laboratory: demonstration of acid-fast bacilli (AFB) in a slit-skin smear (SSS) or in a skin biopsy (SB) of skin lesions with loss of sensation and/or nerve biopsy (NB) of thickened peripheral nerves.
Further diagnostic findings may include:

Definitions
The diagnosis of leprosy is made in the presence of one or more of the following criteria [4,19]: ₋ Clinical: definite loss of sensation in a pale (hypopigmented) or reddish skin patch (SP) or a thickened or enlarged peripheral nerve with loss of sensation and/or weakness of the muscles

Statistical Analysis
Descriptive statistics and plots were used to describe the characteristics of the entire cohort. Categorical variables were reported as absolute and relative frequencies, while quantitative variables were presented as mean and standard deviation or median and interquartile range (IQR), depending on the distribution of the variable. All estimations were reported with 95% confidence intervals. The Student's t or Mann-Whitney U test was used to compare the means or medians between groups. Chi-square or Fisher exact test was used to compare the proportions. Statistical significance level was fixed at 5% (Bonferroni correction was used in case of multiple comparisons). Data analysis was performed with SAS software version 9.4 (Cary, NC, USA).
Our data analysis was further discussed using the results of the literature review and nationwide reports describing migrants with leprosy in European countries in the study period.

Case Series
Sixty-five patients (57 migrants and eight Italians) with a diagnosis of leprosy were seen from January 2009 to December 2018. Demographic and epidemiologic data and clinical features were retrieved for 55 out of 57 migrants (Table 1). Two-thirds were males and the median age was 33 years. The continents of origin were Africa (42%), Asia (40%), and South and Central America (18%). The most reported countries were Sri Lanka (nine patients), Senegal (eight patients), Brazil (seven patients), Nigeria (six patients), and Philippines (five patients), followed by Bangladesh, Cuba, Egypt, India (three patients each country), Pakistan (two patients). Ivory Coast, Gambia, Ghana, Guinea, Morocco, and Togo contributed with one patient each.    An edema of the face (Figure 4a,b) or extremities was observed in four patients, an ocular involvement in three, while fever, arthritis, and lymphadenopathy were observed in two patients each.
Seven patients had already developed some complications: claw deformity, ulcer ( Figure 5), or amputation of fingers or motor deficit (reduced ability to use the hand) (Supplementary Video S1: deficit of abduction of the fifth finger), and difficulty in walking. The skin lesions were further differentiated (not reported in table) in skin patches (24/50 patients, 48%) (Figure 2), papules or nodules (21 patients, 42%), erythema nodosum (five patients, 10%), or ulcers (one patient, 2%). Most of the patches, papules, and nodules were multiple (100%, 79%, and 95%, respectively). The body areas predominantly of interest were (for the 42 patients for whom the data were available): the extremities (27/42), the face (13/42), and the trunk (3/42). In one case, the skin lesions affected the whole body.  An edema of the face (Figure 4a,b) or extremities was observed in four patients, an ocular involvement in three, while fever, arthritis, and lymphadenopathy were observed in two patients each.   Diagnosis. Twenty patients (37% of the 54 who submitted to a nasal swab) were acid-fast bacilli positive, and so were 39 of the 43 patients submitted to slit-skin smear (71%), and 13 of the 43 patients submitted to skin or nerve biopsy (30%). Histological findings of the 43 biopsies highlighted a granulomatous infiltrate in 21 patients (49%) and a lymphocitic or lympho-histiocytic infiltrate in 19 (44%), while three biopsies (7%) were lacking any patent pathological finding. The PCR for M. leprae and M. lepromatosis was performed on 24 patients (on SSS or biopsy), resulting in positive in 17 (85%). A single patient from Cuba with a diagnosis of diffuse lepromatous leprosy associated with Lucio's phenomenon had a positive PCR for M. lepromatosis [21].
The outcome was as follows: 40 patients (73%) successfully completed the treatment, for seven (13%) this was still underway, while eight patients (14%) were lost to follow-up. Forty-seven patients (86%) lived with a variable number of household contacts, for the others, this information was not available.
The outcome was as follows: 40 patients (73%) successfully completed the treatment, for seven (13%) this was still underway, while eight patients (14%) were lost to follow-up. Forty-seven patients (86%) lived with a variable number of household contacts, for the others, this information was not available.

Discussion
We report the main epidemiological and clinical characteristics of 55 cases of leprosy treated in Italy in the decade from 2009 to 2018. In parallel, we reviewed all European cases and case series published in the same decade. The latter of course encompasses a broader timeframe, as many of the cases published were observed earlier than 2009.
Most of the published European cases were diagnosed in Latin American (52%) and African (28%) patients. In contrast, our study population mainly originated from Africa (42%) and Asia (40%). The origin of the published European cases was not uniform across countries, however, while 56% of the cases observed in Portugal were from Africa [22], and 87% and 50% of the cases observed in Denmark and Greece, respectively, were from Asia [8,23]; while in Spain, Latin American patients predominated (72%) [9].
The relatively small number of leprosy reported in Europe and in Italy is in contrast with the increasing wave of migration of the last few decades from endemic countries [10,40,41]. In 1994, the Italian Ministry of Health recognized four national hospitals as reference centers for the diagnosis and cure of leprosy (Genoa, Gioia del Colle, Messina e Cagliari), and in 1999, the Italian guidelines for the control of Hansen's disease were published, indicating the Hospital of Genoa as the reference Italian laboratory for the diagnosis of leprosy (National Reference Center for Hansen Disease, NRCHD) [4]. However, leprosy cases are observed in all Italian regions and only subsequently are they are referred to the reference centers, mostly to NRCHD [14,15]. Therefore, all clinicians dealing with migrants should be able to recognize the symptoms and signs that may raise the suspicion of leprosy, particularly in high-risk populations.
Leprosy is extremely difficult to recognize and it is probably under-diagnosed for a number of reasons, the first one being the lack of knowledge, and therefore of clinical suspicion, by European clinicians. Only a few of them are trained to identify, for instance, the typical skin anesthetic lesions or peripheral nerve (i.e., ulnar) pathology [4]. Moreover, migrants may present with acute diseases such as malaria or with chronic infections that are much easier to suspect and diagnose such as tuberculosis, thus overshadowing the often much more subtle signs and symptoms of leprosy. Furthermore, leprosy can appear with other less common signs that can mimic other diseases [42]. This was also true for some of our patients who presented, for example, with edema of the face or the extremities, eye involvement, fever, arthritis, and lymphadenopathy, hardly attributable to leprosy. The diagnostic work-up is by no means simple, requiring trained experts, usually only available in referral centers, in order to implement the correct diagnostic procedures [4]. The diagnosis is based on a thorough clinical examination plus the combination of all the available tests, considering that their sensitivity is variable. In our patients, AFB was found only in 37% of nasal swab, 71% of SSS, and 30% of biopsies, while a granulomatous inflammation was reported in less than 50% of the cases. Molecular methods are indeed more sensitive, and in Europe, they should always be used on any swab and/or biopsy. In our patients, in the cases when it was performed (about half of the cases), the PCR resulted in being positive in 85%. A Cuban patient with diffuse generalized skin ulcerations caused by M. lepromatosis [21] highlights the need to differentiate the two species of Mycobacterium as they are probably not uncommon [3]. In fact, early diagnosis and full MDT treatment remain the cornerstone of leprosy control, even in non-endemic countries [6]. New guidelines for the diagnosis, treatment, and prevention of leprosy in endemic countries have been issued in 2018 by the WHO [19] and are specifically targeted to low and middle income countries. Unfortunately, no specific guidelines are yet available for the diagnosis and management of imported leprosy in non-endemic countries.
Leprosy is likely to be transmitted via droplets from the nose and the mouth, during close and frequent contacts with MB untreated patients. The first symptoms may appear after a long incubation period (5-10 years) with intermittent symptoms/signs that gradually worsen. In our study, migrant patients were MB in 66% of the cases, similar to the WHO data (60%). The proportion of MB cases indicates, indirectly, the amount of infection in the community. Over 85% of our patients lived in the same house with at least one person that should be considered at risk of acquisition of the infection. The operational manual for the Global Leprosy Strategy 2016-2020 also describes the procedures for contact screening in low endemic settings [43].
Notably, the Asiatic patients in our series were more often MB (77%), had a higher proportion of AFB positive nasal swab and SSS (52% and 82%, respectively) as well as granulomatous infiltrate in the biopsies (69%), and of positive DNA for M. leprae (89%). They also reported, on average, a briefer period of stay in Italy before the diagnosis, which may be assumed to indicate an easier access to the health system. The average latency between the appearance of signs and symptoms and the diagnosis was about 12 months in our series, shorter than that reported in the United Kingdom (1.8 years) [44]. However, in our African population, this reached 26 months. The reasons of this difference should be studied in order to improve the access to early diagnosis in this growing, generally young, high-risk population as barriers of language, culture, and/or law may have made the access to health care more problematic.
The WHO is actively promoting the health of refugees and migrants [45]. Leprosy should be diagnosed at the initial stage when the skin lesions are the predominant manifestations, in order to prevent evolution to the neurological stage. The peripheral neuropathy slowly leads to a progressive sensory loss that makes patients susceptible to inadvertent injuries, leading to foot ulcers, physical deformities, and grade-2 disabilities (G2D) [1,43,46]. Considering that refugees and immigrants are usually young, the prevention of the late complications by early diagnosis and treatment should be a priority.
Clinicians dealing with immigrants from endemic countries should at least be trained to the systematic identification of suspect skin lesions and to the palpation of peripheral nerves (more commonly ulnar and peroneal nerves) for enlargement or pain. Molecular diagnosis should be available in all referral centers, and research is also needed to identify useful markers of infections as well as of cure.
In conclusion, the diagnosis and management of leprosy in refugees and migrants from endemic countries is a challenge. We hope that this neglected disease will gain the necessary consideration among the health problems of refugees and migrants in Europe.