Efficacy and safety of clarithromycin as treatment for Mediterranean spotted fever in children: a randomized controlled trial

Rickettsiales in Italy

There is no updated information on the spread of Rickettsiales in Italy. The purpose of our study is to take stock of the situation on Rickettsiales in Italy by focusing attention on the species identified by molecular methods in humans, in bloodsucking arthropods that could potentially attack humans, and in animals, possible hosts of these Rickettsiales. A computerized search without language restriction was conducted using PubMed updated as of December 31, 2020. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) methodology was followed. Overall, 36 species of microorganisms belonging to Rickettsiales were found. The only species identified in human tissues were Anaplasma phagocytophilum,Rickettsia conorii, R. conorii subsp. israelensis, R. monacensis, R. massiliae, and R. slovaca. Microorganisms transmissible by bloodsucking arthropods could cause humans pathologies not yet well characterized. It should become routine to study the pathogens present in ticks that have bitten a man and at the same time that molecular studies for the search for Rickettsiales can be performed routinely in people who have suffered bites from bloodsucking arthropods.

Epidemiology, Clinical Aspects, Laboratory Diagnosis and Treatment of Rickettsial Diseases in the Mediterranean Area During COVID-19 Pandemic: A Review of the Literature

The purpose of the present review is to give an update regarding the classification, epidemiology, clinical manifestation, diagnoses, and treatment of the Rickettsial diseases present in the Mediterranean area.

We performed a comprehensive search, through electronic databases (Pubmed – MEDLINE) and search engines (Google Scholar), of peer-reviewed publications (articles, reviews, and books).

The availability of new diagnostic tools, including Polymerase Chain Reaction and nucleotide sequencing has significantly modified the classification of intracellular bacteria, including the order Rickettsiales with more and more new Rickettsia species recognized as human pathogens. Furthermore, emerging Rickettsia species have been found in several countries and are often associated with unique clinical pictures that may challenge the physician in the early detection of the diseases.

Rickettsial infections include a wide spectrum of clinical presentations ranging from a benign to a potentially life treating disease that requires prompt recognition and proper management. Recently, due to the spread of SARS-CoV-2 infection, the differential diagnosis with COVID-19 is of crucial importance. The correct understanding of the clinical features, diagnostic tools, and proper treatment can assist clinicians in the management of Rickettsioses in the Mediterranean area.

Rickettsial infections of the central nervous system

As a result of migrations and globalization, people may face a possible increase in the incidence of central nervous system rickettsial infections (CNS R). These diseases, caused by Rickettsia species and transmitted to humans by arthropod bites, are putatively lethal. However, the diagnosis of CNS R is challenging and often delayed due to their nonspecific clinical presentation and the strict intracellular nature of rickettsiae. Furthermore, transfer of rickettsiae to the brain parenchyma is not yet understood. The aim of this review is to analyze and summarize the features and correlated findings of CNS R in order to focus attention on these intriguing but frequently neglected illnesses. We also incorporated data on CNS infections caused by Rickettsia-related microorganisms.

Evaluating Safety Reporting in Paediatric Antibiotic Trials, 2000-2016: A Systematic Review and Meta-Analysis

BACKGROUND

There are very few options to treat multidrug-resistant bacterial infections in children. A major barrier is the duration and complexity of regulatory trials of new antibiotics. Extrapolation of safety data from adult trials could facilitate drug development for children.

OBJECTIVE

We performed a systematic review on the safety of antibiotic clinical trials (CTs) in children (0-18 years) to evaluate the overall quality of safety trials conducted in children and to determine if age-specific adverse events (AEs) could be identified for specific antibiotic classes.

DATA SOURCES

We searched the MEDLINE, Cochrane CENTRAL, and ClinicalTrials.gov electronic databases for trials conducted between 2000 and 2016.

STUDY SELECTION

All trials in which safety was declared a primary or secondary endpoint were included. Exclusion criteria were (1) topical or inhalational route of administration; (2) non-infectious conditions; (3) administration for prophylaxis rather than treatment; (4) selected population (i.e. cystic fibrosis, malignancies, HIV and tuberculosis); and (5) design other than randomized controlled trials. Trials reporting data on both adults and children were included only if paediatric results were reported separately.

DATA EXTRACTION AND SYNTHESIS

Two authors independently extracted the data. To assess the quality of published trials, the Extension for harms for Consolidated Standards of Reporting Trials (CONSORT) Statement 2004 was used.

MAIN OUTCOME AND MEASURE

In order to quantitatively assess the rate of developing AEs by drug class, the numbers of overall and body-system-specific AEs were collected for each study arm, and then calculated per single drug class as median and interquartile range (IQR) of the proportions across CTs. The AEs most frequently reported were compared in the meta-analysis by selecting the CTs on the most represented drug classes.

RESULTS

Eighty-three CTs were included, accounting for 27,693 children. Overall, 69.7% of CONSORT items were fully reported. The median proportion of children with any AE was 22.5%, but did not exceed 8% in any single body system. Serious drug-related AEs and drug-related discontinuations were very rare (median 0.3 and 0.9%, respectively). Limitations included the inability to stratify by age group, particularly neonates.

CONCLUSIONS AND RELEVANCE

Overall, AEs in paediatric antibiotic CTs were predictable and class-specific, and no unexpected (age-specific) side effects were identified. Smaller, open-label, dose-finding, high-quality, single-arm pharmacokinetic trials seem potentially sufficient for certain common antibiotic classes, extrapolating well-established safety profiles determined from large adult efficacy trials. This approach could reduce duration and enhance subsequent registration of urgently needed new antibiotics. This will need to be combined with enhanced methods of pharmacovigilance for monitoring of emerging AEs in routine clinical practice.

Clinically-diagnosed Mediterranean Spotted Fever in Malta

BACKGROUND

Mediterranean Spotted Fever (MSF) is a tick-borne zoonosis caused by Rickettsia conorii which is endemic in Malta, an island in the South Mediterranean that is a popular tourist destination. Diagnosis is frequently based on clinical manifestations as laboratory results are often limited to a retrospective diagnosis. We describe the clinical presentation, diagnosis and treatment of children <16 years who presented with MSF from 2011 to 2016.

METHOD

The demographics, clinical findings, laboratory results, management and outcome of all children hospitalised with suspected MSF based on the presence of fever and an eschar, were retrieved from their case notes.

RESULTS

Over the five-year study period six children, aged between 17 months and 15 years, were diagnosed with MSF. All children had contact with ticks and the majority presented in summer. Laboratory results were non-specific and included elevated inflammatory markers, lymphocytosis/lymphopenia and hyponatraemia. Serological and molecular techniques were used for diagnosis. Response to clarithromycin or doxycycline was immediate.

CONCLUSION

MSF should be included in the differential diagnosis of fever, rash and an eschar in children who travel to Malta. Despite advances in molecular diagnostics, clinical diagnosis remains important in the management of children with suspected MSF.

Israeli Spotted Fever in Sicily. Description of two cases and minireview

Mediterranean spotted fever (MSF) is endemic in Italy, where Rickettsia conorii subsp. conorii was thought to be the only pathogenic rickettsia and Rhipicephalus sanguineus the vector and main reservoir. R. conorii subsp. israelensis, which belongs to the R. conorii complex, is the agent of Israeli spotted fever (ISF); apart from Israel, it has also been found in Italy (Sicily and Sardinia) and in different regions of Portugal. We describe here two severe cases of ISF which occurred in otherwise healthy Italian adults. Their characteristics are analyzed and discussed in the light of other 91 cases found through a systematic review of international literature.

Myocarditis in Mediterranean spotted fever: a case report and a review of the literature

INTRODUCTION

Mediterranean spotted fever (MSF) is a tick-borne acute febrile disease caused by Rickettsia conorii. Most cases follow a benign course, with a case fatality rate of 3-7 % among hospitalized patients. Complications are described mainly in adult patients and include hepatic, renal, neurological and cardiac impairment. Among cardiac complications, pericarditis, myocarditis and heart rhythm disorders are uncommon complications in MSF and only a few cases have been reported in the literature.

CASE PRESENTATION

We describe a new case of acute myocarditis complicating MSF in an immunocompetent adult patient without risk factors for severe MSF.

CONCLUSION

Myocarditis is an uncommon but severe complication of MSF. Clinicians should be aware of a possible cardiac involvement in patients with MSF. Close monitoring and an aggressive approach are essential to reduce mortality rates of MSF.

A Rare Case of Mediterranean Spotted Fever and Encephalitis

Mediterranean spotted fever is a tick-borne zoonotic disease caused by Rickettsia conorii. It is transmitted by the dog tick Rhipicephalus sanguineus. It usually presents as a benign self-limited disease characterized by a skin rash, high fever, and, sometimes, a characteristic ulcer at the tick bite site called tache noir. The course of this disease is usually benign, although severe manifestations have been previously described, mainly in adults. Neurological manifestations are very unusual. We present a case of Mediterranean spotted fever with encephalitis to highlight the importance of clinical suspicion, mainly in endemic areas, the potential severity of this disease, and the need of early initiation of therapy in order to prevent severe complications.

Randomized Trial of Clarithromycin for Mediterranean Spotted Fever

The classic antibiotic treatment for Mediterranean spotted fever (MSF) is based on tetracyclines or chloramphenicol, but chloramphenicol's bone marrow toxicity makes tetracyclines the treatment of choice. However, it is convenient to have alternatives available for patients who are allergic to tetracyclines, pregnant women, and children <8 years old. We conducted a randomized clinical trial to compare clarithromycin with doxycycline or josamycin in the treatment of MSF. Forty patients were evaluated (23 male; mean age, 39.87 years); 13 patients were aged <14 years. Seventeen patients received clarithromycin, and 23 received doxycycline or josamycin. The interval between the onset of symptoms and the start of treatment was 4.04 ± 1.70 days in the clarithromycin group versus 4.11 ± 1.60 days in the doxycycline/josamycin group (P = not significant [NS]). Time to the disappearance of fever after treatment was 2.67 ± 1.55 days in the clarithromycin group versus 2.22 ± 1.35 days in the doxycycline/josamycin (P = NS). The symptoms had disappeared at 4.70 ± 2.25 days in the clarithromycin group versus at 4.75 ± 3.08 days in the doxycycline/josamycin (P = NS). There were no adverse reactions to treatment or relapses in either group. In conclusion, clarithromycin is a good alternative to doxycycline or josamycin in the treatment of MSF.

Efficacy and safety of chloramphenicol: joining the revival of old antibiotics? Systematic review and meta-analysis of randomized controlled trials

OBJECTIVES

Chloramphenicol is an old broad-spectrum antibiotic. We assessed its efficacy and safety.

METHODS

This was a systematic review and meta-analysis. Electronic databases were searched to identify randomized controlled trials (RCTs) that assessed patients, of any age, with systemic bacterial infections that can cause sepsis and compared chloramphenicol alone versus other antibiotics. No restrictions on the date of publication, language or publication status were applied. The primary outcome assessed was overall mortality.

RESULTS

Sixty-six RCTs fulfilled the inclusion criteria, and these included 9711 patients. We found a higher mortality with chloramphenicol for respiratory tract infections [risk ratio (RR) 1.40, 95% CI 1.00-1.97] and meningitis (RR 1.27, 95% CI 1.00-1.60), both without heterogeneity. The point estimate was similar for enteric fever, without statistical significance. No statistically significant difference was found between chloramphenicol and other antibiotics regarding treatment failure, except for enteric fever (RR 1.46, 95% CI 1.07-2.00, without heterogeneity). This difference derived mainly from studies comparing chloramphenicol with fluoroquinolones (RR 1.85, 95% CI 1.07-3.2). There were no statistically significant differences between chloramphenicol and other antibiotics in terms of adverse events, including haematological events, except for anaemia, which occurred more frequently with chloramphenicol (RR 2.80, 95% CI 1.65-4.75, I(2) =0%), and gastrointestinal side effects, which were less frequent with chloramphenicol (RR 0.67, 95% CI 0.46-0.99, I(2) =0%). Many of the studies included were sponsored by pharmaceutical companies marketing the comparator drug to chloramphenicol, and this might have influenced the results.

CONCLUSIONS

Chloramphenicol cannot be recommended as a first-line treatment for respiratory tract infections, meningitis or enteric fever as alternatives are probably more effective. Chloramphenicol is as safe as treatment alternatives for short antibiotic courses. RCTs are needed to test this treatment against MDR organisms when better alternatives do not exist.

Treatment of Rickettsia spp. infections: a review

Human rickettsioses caused by intracellular bacteria of the genus Rickettsia are distributed worldwide and are transmitted by arthropod vectors such as ticks, fleas, mites and lice. They have a wide range of manifestations from benign to life-threatening diseases. Mortality rates of up to 30% have been reported for some rickettsioses. Here, the authors will review in vitro and human studies of the various compounds that have been used for the treatment of Rickettsia spp. infections. The authors will also provide recommendations for the treatment of spotted fever and typhus group rickettsioses.

Antimicrobial prevention and therapy for travelers' infection

International journeys are increasing and more than 70 million people from industrialized countries cross the borders of tropical countries every year. More than 50% of them will suffer from some form of infectious illness, ranging from mild travelers' diarrhea to severe dengue fever to fatal malaria, with a wide spectrum of microbiological entities. Travel-related respiratory infections, including TB, and sexually transmitted infections are also increasingly reported. Awareness of travel-related risk is not always adequate among international travelers. Specific training on travel medicine-related issues, as well as better diagnostic facilities for imported diseases, is crucial for physicians and nurses in industrialized countries.

Mediterranean spotted fever: clinical and laboratory characteristics of 415 Sicilian children

BACKGROUND

Mediterranean spotted fever (MSF) is an acute febrile, zoonotic disease caused by Rickettsia conorii and transmitted to humans by the brown dogtick Rhipicephalus sanguineus. Nearly four hundred cases are reported every year (mainly from June to September) on the Italian island of Sicily. The aim of the study was to analyze the clinical and laboratory characteristics of patients with MSF and the efficacy of the drugs administered.

METHODS

Our study was carried out on 415 children with MSF, during the period January 1997-December 2004, at the "G. Di Cristina" Children's hospital in Palermo, Sicily, Italy. On admission patients' clinical history, physical and laboratory examination and indirect immunofluorescence antibody test (IFAT) for Rickettsia conorii were performed. Diagnosis was considered confirmed if the patients had an MSF diagnostic score greater than or equal to 25 according to the Raoult's scoring system. All patients were treated with chloramphenicol or with macrolides (clarithromycin or azithromycin).

RESULTS

Fever, rash and tache noire were present in 386 (93%), 392 (94.5%) and 263 (63.4%) cases respectively. Eighteen (4.6%) children showed atypical exanthema. Chloramphenicol and newer macrolides all appeared to be effective and safe therapies.

CONCLUSION

Clinical features of 415 children with MSF were similar to those reported by other authors except for a lower incidence of headache, arthralgia and myalgia and a higher frequency of epato-splenomegaly. Concerning therapy, clarithromycin can be considered a valid alternative therapy to tetracyclines or chloramphenicol especially for children aged < eight years.

A new focus of Rickettsia honei spotted fever in South Australia

We recently diagnosed rickettsial spotted fever in four patients from the south-eastern coastal region of South Australia near Adelaide, an area not known to be endemic for this infection. All infections were acquired within the geographic range of Aponomma hydrosauri, the tick vector of Rickettsia honei. Infection by R. honei was confirmed in two patients. This extension of the known geographic range of R. honei infection may be explained, in part, by alterations in host-parasite ecology.

Rickettsial infections around the world, part 1: pathophysiology and the spotted fever group

BACKGROUND

The rickettsial diseases are an important group of infectious agents that have dermatological manifestations. These diseases are important to consider in endemic areas, but in certain suspicious cases, possible acts of bioterrorism should warrant prompt notification of the appropriate authorities.

OBJECTIVE

In this two part review article, we review these diverse diseases by examining established and up-to-date information about the pathophysiology, epidemiology, clinical manifestations, and treatment of the ricksettsiae.

METHODS

Using PubMed to search for relevant articles, we browsed over 500 articles to compose a clinically based review article.

RESULTS

Part one focuses on pathophysiology of the rickettsial diseases and the clinical aspects of the spotted fever group.

CONCLUSIONS

At the completion of part one of this learning activity, participants should be able to discuss all of the clinical manifestations and treatments of the sported fever group. Participants should also be familiar with the pathophysiology of the rickettsial diseases.

Tick-borne rickettsioses around the world: emerging diseases challenging old concepts

During most of the 20th century, the epidemiology of tick-borne rickettsioses could be summarized as the occurrence of a single pathogenic rickettsia on each continent. An element of this paradigm suggested that the many other characterized and noncharacterized rickettsiae isolated from ticks were not pathogenic to humans. In this context, it was considered that relatively few tick-borne rickettsiae caused human disease. This concept was modified extensively from 1984 through 2005 by the identification of at least 11 additional rickettsial species or subspecies that cause tick-borne rickettsioses around the world. Of these agents, seven were initially isolated from ticks, often years or decades before a definitive association with human disease was established. We present here the tick-borne rickettsioses described through 2005 and focus on the epidemiological circumstances that have played a role in the emergence of the newly recognized diseases.

Rickettsial Infections around the World, Part 1: Pathophysiology and the Spotted Fever Group

Background:

The rickettsial diseases are an important group of infectious agents that have dermatological manifestations. These diseases are important to consider in endemic areas, but in certain suspicious cases, possible acts of bioterrorism should warrant prompt notification of the appropriate authorities.

Objective:

In this two part review article, we review these diverse diseases by examining established and up-to-date information about the pathophysiology, epidemiology, clinical manifestations, and treatment of the ricksettsiae.

Methods:

Using PubMed to search for relevant articles, we browsed over 500 articles to compose a clinically based review article.

Results:

Part one focuses on pathophysiology of the rickettsial diseases and the clinical aspects of the spotted fever group.

Conclusions:

At the completion of part one of this learning activity, participants should be able to discuss all of the clinical manifestations and treatments of the sported fever group. Participants should also be familiar with the pathophysiology of the rickettsial diseases.

Dermatologic infectious diseases in international travelers

Skin lesions provide an important clue to the diagnoses of many infections in returned travelers. New information related to epidemiology, recognition, diagnosis, or management is described for the systemic infections--dengue fever, several of the rickettsial infections, African trypanosomiasis, and coccidioidomycosis. Many pathogens cause focal skin findings. Recent findings are presented for cutaneous leishmaniasis, Buruli ulcer, gnatho-stomiasis, cutaneous larva migrans, myiasis, tungiasis, and scabies. This paper describes the most common skin problems in returning travelers and outlines the types of infections that cause skin lesions, as defined by morphologic characteristics.

Clarithromycin versus azithromycin in the treatment of Mediterranean spotted fever in children: a randomized controlled trial

We conducted an open-label randomized controlled trial to compare the efficacy and safety of clarithromycin (15/mg/kg/day in 2 divided doses for 7 days) with those of azithromycin (10 mg/kg/day in 1 dose for 3 days) in the treatment of children with Mediterranean spotted fever. Until now, there has not been a gold-standard therapy for this rickettsial disease in children. Eighty-seven children were randomized to receive 1 of the 2 drugs. The mean time to defervescence (+/- standard deviation) was 46.2+/-36.4 h in the clarithromycin group and 39.3+/-31.3 h in the azithromycin group. These differences were not statistically significant and both drugs were equally well-tolerated. Clarithromycin and azithromycin could be acceptable therapeutic alternatives to chloramphenicol and tetracyclines for children aged < or =8 years with Mediterranean spotted fever. Azithromycin, because it has a long half-life, offers the advantages of administration in a single daily dose and a shorter duration of therapy, which could increase compliance in children.