Lidija Lavadinovic

Imported malaria in Belgrade, Serbia, between 2001 and 2009

ZusammenfassungSeit 2000 steigt die Zahl serbischer Bürger, die Reisen in die Tropen machen, langsam aber ständig. Um die epidemiologischen und klinischen Charakteristika der nach Serbien verschleppten Malaria zu erfassen, analysierten wir die klinische Anamnese aller Reisenden, die sich nach der Rückkehr aus tropischen oder subtropischen Gebieten zwischen 2001 und 2009 am Institut für Infektionen und Tropenkrankheiten in Belgrad vorstellten. Insgesamt wurden 2981 Reisende erfasst, von denen 847 gesundheitliche Probleme hatten. Eine Malaria wurde bei 102 (3,4 % aller Reisenden; 12 % aller Reisenden mit Fieberschüben) diagnostiziert. Mit einer Inzidenzrate von 6-16 Fälle pro Jahr wurde die Malaria hauptsächlich aus Afrika (92,2 %), vor allem Äquatorial Guinea (38,2 %) und Nigeria (15,7 %) eingeschleppt. Der häufigste Grund für die Reisen war geschäftlich, beziehungsweise beruflich. Die Patienten waren zumeist Männer (87,3 %) in einem Alter großteils zwischen 40 und 59 Jahren (66,7 %). Insgesamt nahmen 15 der erkrankten Personen (14,7 %) irgendeine Form einer Malariaprophylaxe ein. Plasmodium (P) falciparum (78), alleine (70) oder gemischt mit P. vivax (5) war die häufigste ursächliche Spezies. P. vivax, P. ovale und P. malariae konnten in 11, 1 und 1 der Fälle als alleiniger Erreger nachgewiesen werden. Von den 11 Fällen, in denen der Parasit nicht gefunden wurde, schienen sechs echte submikroskopische Fälle zu sein. Der klinische Verlauf war bei 13 Patienten (alle mit P. falciparum infiziert) schwer. Drei dieser Patienten (2,9 %) verstarben. Screening auf Malaria sollte in Serbien für in endemische Regionen Reisende, die sich mit Fieber präsentieren, (unabhängig davon, ob sie eine Chemoprophylaxe einnehmen oder nicht), verpflichtend sein. Nicht ausreichende Sensitivität der konventionellen Methoden (wie wir sie bei den submikroskopischen Fällen beobachtet haben) erfordert die Einführung molekularer Diagnostik in die Routinepraxis.SummarySince 2000, travel of Serbian citizens to tropical areas has been slowly but steadily increasing. To determine the epidemiological and clinical characteristics of imported malaria in Serbia, we analyzed clinical history data of all travelers who presented at the Clinic for Infectious and Tropical Diseases in Belgrade after their return from tropical and subtropical areas between 2001 and 2009. The study series involved a total of 2981 travelers, and included both those with (847) and without (2134) health problems. Malaria was diagnosed in 102 cases (3.4% of all travelers; 12.0% of travelers with febrile episodes). Occurring at a rate of 6 to 16 cases per year, it was predominantly imported from Africa (92.2%), particularly from Equatorial Guinea (38.2%) and Nigeria (15.7%). The most frequent reason for travel was work/business. Patients were predominantly (87.3%) male, and the majority (66.7%) was between 40 and 59 years of age. A total of 15 (14.7%) patients took some form of anti-malarial chemoprophylaxis. The dominant causative species was Plasmodium falciparum (78), alone (70) or in mixed infection with P. vivax (5) and P. malariae (3). P. vivax, P. ovale and P. malariae as single agents were each identified in 11, 1 and 1 cases, respectively. Of the 11 cases in which the parasite was not detected, six appeared to be true submicroscopic cases. The clinical course of the disease was severe in 13 patients, all with falciparum malaria, of which three (2.9%) died. Rather than for all travelers, in Serbia screening for malaria should be mandatory in all travelers to endemic regions who present with fever irrespective of chemoprophylaxis history. Inadequate sensitivity of conventional diagnostic methods, illustrated by the cases of submicroscopic malaria, requires introduction of molecular diagnosis in routine practice.

Clinical significance of molecular methods in the diagnosis of imported malaria in returning travelers in Serbia

OBJECTIVES The goal of this study was to assess the clinical significance of conventional and PCR-based molecular diagnosis in patients with imported malaria in Serbia. METHODS Giemsa microscopy, the rapid diagnostic test, and quantitative real-time PCR (qPCR) were used to detect Plasmodium species in 109 whole-blood samples from patients after their return from malaria endemic areas, including those clinically suspected for malaria (n=97) and healthy travelers (n=12) examined as part of epidemiological surveillance. RESULTS A total of 45 patients were diagnosed with malaria: 42 (93.3%) by microscopy and three (6.7%) additional ones by qPCR. The agreement between the results of species-specific qPCR and microscopy was 73.3%; it was as high as 90.6% for Plasmodium falciparum infections. Follow-up analysis demonstrated persistence of Plasmodium sp DNA for a mean 6 days after the disappearance of parasitemia on microscopy. CONCLUSIONS Due to its sensitivity and specificity, qPCR is a helpful method complementary to microscopy, particularly in cases of low parasitemia. In addition, it is superior to microscopy for species identification.

Non-specific inflammatory parameters in patients with pandemic H1N1 influenza.

The measurement of non-specific inflammation parameters, such as erythrocyte sedimentation rate (ESR), fibrinogen, C-reactive protein (CRP) and procalctinon (PCT) are very important tools for diagnosis of infections, as well as for monitoring of treatment response. The aim of this study was to determine the significance of non-specific inflammatory parameters in patients with influenza H1N1 infection. ESR, fibrinogen, CRP and PCT were analyzed in patients with influenza H1N1 infection. The diagnosis of influenza H1N1 was established from the nasopharyngeal swabs using Real Time Polymerase Chain Reaction - (RT PCR) method. Chest X-ray was performed to diagnose pneumonia Sixty-three out of 340 hospitalized patients with influenza had pandemic influenza. Their mean age was 34.60±13.82 years. They were referred to hospital 1 to 7 (4.06±2.0) days after onset of symptoms. Of these, 46 had pneumonia, while the majority (41 patients) had interstitial pneumonia, and only five had lobar or segmental pneumonia. Patients with pneumonia had significantly higher levels of CRP and PCT in comparison with those without pneumonia. Patients with lobar pneumonia had significantly higher CRP than those with interstitial pneumonia. However, mean values of PCT between interstitial and lobar pneumonia cases did not differ significantly. Interstitial pneumonia was the most common complication of H1N1 infection among our patients. Non-specific parameters of inflammation, especially CRP and PCT were increased in all pneumonia cases, regardless of the etiology. Monitoring of non-specific inflammatory parameters in patients with H1N1 infection allows recognition of patients with complications, their prompt hospitalization and early initiation of antimicrobial therapy.

Imported parasitic infections in Serbia

BACKGROUND Travel to the tropics is associated with a risk of parasitic infection, which is increasing in parallel with the rise in travel to these areas. We thus examined the prevalence and trend in the occurrence of parasitic infections in Serbian travelers. METHODS A retrospective analysis of the medical records of all travelers returning from tropical and subtropical areas, who presented at the Institute for Infectious and Tropical Diseases in Belgrade between January 2001 and January 2008, was performed. RESULTS Of a total of 2440 travelers, 169 (6.9%) were diagnosed with a parasitic infection, including malaria in 79, intestinal parasites in 84 (pathogenic species in 30 and non-pathogenic in 54), filariasis in four, and visceral leishmaniasis and fascioliasis in one patient each. Importantly, of the whole series only 583 (23.9%) were symptomatic, of which 19.4% were found to be infected with a parasite. The single pathogenic parasite occurring in asymptomatic patients was Giardia intestinalis. CONCLUSIONS Parasitic infection causing symptomatic disease among travelers returning from tropical areas to Serbia is not infrequent. In view of the expected increase in travel to the tropics, diagnostic protocols for tropical parasitic diseases should take these data into account.

Safety and immunogenicity of a seasonal trivalent inactivated split influenza vaccine: a phase I randomized clinical trial in healthy Serbian adults

ABSTRACT This study was a phase I double-blind, randomized, placebo-controlled trial to evaluate the safety and immunogenicity of a Serbian-produced seasonal trivalent split, inactivated influenza vaccine in healthy adults. The vaccine was manufactured in eggs by the Torlak Institute of Virology, Vaccines and Sera, Belgrade, Serbia and contained A/H1N1, A/H3N2 and B viruses. The clinical trial took place at the Clinical Center of Serbia in Belgrade. Sixty healthy volunteers, aged 18–45 years, were enrolled in the trial. On the day of immunization, volunteers were randomly assigned to receive either a single dose of the trivalent seasonal influenza vaccine (15 μg of hemagglutinin per strain) or placebo (phosphate-buffered saline). Subjects were monitored for adverse events through a clinical history and physical examination, and blood was taken for testing at screening and on day 8 to assess vaccine safety. Serum samples obtained before and 21 days after immunization were tested for influenza antibody titers using hemagglutination-inhibition (HAI) and microneutralization (MN) tests. No serious adverse events were reported. Pain and tenderness at the injection site were the most commonly reported symptoms in both vaccine and placebo groups. Overall, serum HAI responses of fourfold or greater magnitude were observed to H1, H3, and B antigen in 80%, 75%, and 70% of subjects, respectively. Seroprotection rates as measured by HAI were also high (100%, 100% and 86.67%, respectively, for H1, H3 and B). Thus, Torlaks seasonal trivalent influenza vaccine was not associated with adverse events, was well-tolerated and immunogenic. It should be further evaluated in clinical trials to provide sufficient safety and immunogenicity data for licensing in Serbia.

Clinical characteristics of imported malaria: An 11-year experience in a Serbian referral center

INTRODUCTION Due to intercontinental traffic, population migration trends, natural disasters, and climate change, imported malaria remains important to consider in a febrile returning traveler. This study aims to raise awareness about malaria and help European clinicians maintain a working knowledge of this disease by reviewing the most important clinical characteristics in a non-endemic setting. METHODOLOGY Using medical records, a retrospective study was performed on clinical and laboratory data in order to analyze 103 malaria cases managed at the Clinic for Infectious and Tropical Diseases in Belgrade, from 2000 to 2010. Descriptive statistics, Chi-squared test, Spearmans rank correlation, and analysis of variance were used. RESULTS Patients were predominantly male (89.3%) with a mean age of 46.66 ± 12.45 years, and most (98.06%) returned from Africa without having taken chemoprophylaxis (72.88%). Fever, arthralgia, myalgia, headache, vomiting, dark urine, and cough were common at presentation. Hepatosplenomegaly, jaundice, neurological and pulmonary findings, and thrombocytopenia were dominant findings on physical and laboratory examinations. Most (73.48%) were infected with P. falciparum. Few patients (17.55%) who were hyperparasitemic had significantly higher values of bilirubin and more frequent neurological complications. All patients were treated with artemisinin-based drug combinations regardless of Plasmodium species. Three (2.9%) patients succumbed to P. falciparum malaria. CONCLUSION We suggest a high index of suspicion of malaria be maintained when evaluating febrile patients returning from endemic regions, especially if thrombocytopenia and hemolysis are present. Hyperparasitemia, high bilirubin levels, and neurological symptoms are associated with severe malaria. The importance of adequate malaria chemoprophylaxis cannot be overstated.

Retrospective PCR-based species identification of Leishmania in two patients with visceral leishmaniasis in Serbia

Introduction: Retrospective molecular identification of Leishmania parasites in two patients with visceral leishmaniasis (VL) previously treated in Serbia was carried out. DNA was isolated from unstained bone marrow smears (BMSs) kept for 11 and 8 years. Genus-specific real-time PCR was combined with conventional PCR and sequencing for detection and species identification. Case presentation: In 2003, a 40-year-old Serbian male was admitted to the Clinical Centre of Serbia (CCS) with fever, sweating, fatigue and splenomegaly, which developed over a period of 7 weeks. He had frequently travelled around Europe. VL was confirmed by microscopy of Giemsa-stained BMS. Treatment by pentavalent antimonials was successfully completed. Two years later, the patient developed post-kala-azar dermal leishmaniasis. Treatment resulted in symptom resolution. Later on, Leishmania infantum was identified as the causative agent of the VL by sequencing of the ITS (internal transcribed spacer) region; mixed Leishmania spp. infection could not be excluded. In 2006, a 33-year-old female from Vojvodina, Serbia, with pre-existing diabetes mellitus and chronic meningoencephalitis and a history of frequent visits to the Montenegrin seacoast, was admitted to the CCS with fever, pancytopenia and moderate hepatosplenomegaly. A stained BMS revealed abundant Leishmania amastigotes. Indirect haemagglutination analysis was positive with a titre of 1 : 2048, and a rapid dipstick rK39 test was also positive. Treatment by liposomal amphotericin B was successful; however, shortly after, the patient developed neural infection and pneumonia and died. The causative agent was identified as L. infantum. Conclusion: Molecular diagnosis of VL and species delineation using DNA from unstained BMSs stored for several years is possible.