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

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Review

Israeli

Spotted

Fever

in

Sicily.

Description

of

two

cases

and

minireview

Claudia

Colomba

a,

*

,

Marcello

Trizzino

a

,

Anna

Giammanco

a

,

Celestino

Bonura

a

,

Danilo

Di

Bona

b

,

Manlio

Tolomeo

a

,

Antonio

Cascio

a

DipartimentodiScienzeperlaPromozioneDellaSaluteeMaterno-Infantile,UniversitàdiPalermo,Italy b

Dipartimentodell’EmergenzaedeiTrapiantod’Organo,UniversitàdiBari,Italy

ARTICLE INFO Articlehistory:

Received16February2017

Receivedinrevisedform28March2017 Accepted3April2017

CorrespondingEditor:EskildPetersen, Aar-hus,Denmark

Keywords:

Mediterraneanspottedfever Rickettsiaisraelensis Israelispottedfever

ABSTRACT

Mediterraneanspottedfever(MSF)isendemicinItaly,whereRickettsiaconoriisubsp.conoriiwasthought tobetheonlypathogenicrickettsiaandRhipicephalussanguineusthevectorandmainreservoir.R.conorii subsp.israelensis,whichbelongstotheR.conoriicomplex,istheagentofIsraelispottedfever(ISF);apart fromIsrael,ithasalsobeenfoundinItaly(SicilyandSardinia)andindifferentregionsofPortugal.We describe here two severe cases of ISF which occurred in otherwisehealthy Italian adults. Their characteristicsareanalyzedanddiscussedinthelightofother91casesfoundthroughasystematic reviewofinternationalliterature.

Contents

Introduction ... 7

Case1 ... 8

Case2 ... 8

Literaturereviewanddiscussion ... 8

Conﬂictsofinterest ... 11 Sourcesoffunding ... 11 Ethicalapproval ... 11 Acknowledgements ... 11 References ... 11 Introduction

Rickettsia conorii subsp. israelensis, which belongs to the R. conoriicomplex,istheagentofIsraelispottedfever(ISF).Itwas ﬁrstreported in1974 in Israeland distribution appearedto be

restrictedonlytothatcountry(Goldwasseretal.,1974; Mumcuo-gluetal.,2002).

Several cases of postmortem diagnosis of ISF have been described in children and adults in Israel using cell culture methods,animalinoculationandimmunohistochemicaldetection of rickettsial antigen in parafﬁn-embedded tissue obtained at autopsy (Yagupskyand Wolach,1993;Aharonowitzet al.,1999

Aharonowitzetal.,1999).OnlylaterwasnestedPCRappliedtosera andtissueinseveralfatalcasesofrickettsialinfectionsandshown tobeeffectiveinestablishingthecorrectdiagnosis(Schattneretal., 1992;Keysaryetal.,2007;Weinbergeretal.,2008).

Rickettsia conorii subsp. conorii was thought to be the only pathogenicrickettsiaofthespottedfevergroupinEuropewhereit is endemicinsouthern Europe,withsporadic casesreportedin northernandcentralEurope.Rhipicephalussanguineusisthevector and a potential reservoir of R. conorii subsp. conorii in the

Abbreviations:MSF,Mediterraneanspottedfever;ISF,Israelispottedfever;PCR, Polymerasechainreaction;MRI,Magneticresonanceimaging;ICU,intensivecare unit;IFA,Immunoﬂuorescenceassay;ELISA,enzyme-linkedimmunosorbentassay; n.v.,normalvalue;NA,notavailable.

* Correspondingauthor.Telephone+390916554054,Fax+390916554050. E-mailaddresses:claudia.colomba@libero.it(C.Colomba),

marcellotrizzino@hotmail.it(M.Trizzino),anna.giammanco@unipa.it

(A.Giammanco),celestino.bonura@unipa.it(C.Bonura),danilo.dibona@uniba.it

(D.DiBona),mtolomeo@hotmail.com(M.Tolomeo),antonio.cascio03@unipa.it

(A.Cascio).

http://dx.doi.org/10.1016/j.ijid.2017.04.003

1201-9712/©2017TheAuthors.PublishedbyElsevierLtdonbehalfofInternationalSocietyforInfectiousDiseases.ThisisanopenaccessarticleundertheCCBY-NC-ND license(http://creativecommons.org/licenses/by-nc-nd/4.0/).

InternationalJournalofInfectiousDiseases61(2017)7–12

ContentslistsavailableatScienceDirect

International

Journal

of

Infectious

Diseases

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Mediterranean area. However, in the last few decades, newly recognizedtick-bornerickettsioseshavebeenshowntobepresent inEurope(Parolaetal.,2013),andR.conoriisubsp.israelensishas alsobeendetectedinRhipicephalussanguineusandinhumancases inSicily and Sardinia,Italy and indifferent regionsof Portugal (Giammanco etal., 2003;Chisuet al.,2014; Giammancoet al., 2005a;Bacellaretal.,1999;Bacellaretal., 1995;Amaroetal.,2003; DeSousaetal.,2003a;DeSousaetal.,2008;DeSousaetal.,2005). Every year, about 300 cases of Mediterraneanspotted fever (MSF)arenotiﬁed(mainlyfromJunethroughSeptember)inthe ItalianislandofSicily.

MSF istypicallycharacterizedbyfever,skinrashandablack escharatthesiteofthetickbite(“tachenoire”)(Cascioetal.,2001; Colombaetal.,2006Colombaetal.,2006).

WereportheretwocasesofISFinotherwisehealthySicilian adultsandreviewallarticlesdescribingcasesofISFinwhichthe diagnosiswasmadeusingmolecularbiologytechniques. Case1

A45-year-oldRomanianman,inItalyforﬁveyears,previously healthy, except for a treated pulmonary tuberculosis tenyears before,wasadmittedtoPalermoUniversityHospital,Italy,inJuly 2016 for an history of fever (39C), headache, mialgia and weakness for 5 days. One day before admission a generalized rashdeveloped.Thepatientwasanalcoholicandlivedinarural environmentinSicilyandownedadog.

Onadmission,hewasfebrile(38.9C),tachycardic(120/min), tachypnoeic(40/min),oliguricandcomplainedofseveremuscle pain.Aphysicalexaminationshoweddiffusemacularrashonthe trunkand extremities,includingpalmsandsoles. Thedayafter admission,afewpetechiallesionsappearedonhislegs.Laboratory investigations yielded the following results: C-reactive protein level253mg/L(n.v.<5mg/L);leukocytecount,5.9109_/L;_platelet

counts,13109_/L; _creatinine_1.08_mg/dL;_aspartate

aminotrans-ferase, 464U/L; alanine aminotransferase, 126U/L;

g

-glutamyl-transpeptidase, 45U/L; pH 7.45; lactate, 2.5mmol/L; D-dimer, 19.000ng/mL (n.v. 10–250ng/mL). Routine blood and urine cultures, serologic tests for HIV, Leptospira spp. and Rickettsia spp. were performed but the results were not diagnostic. Treatmentwithintravenouspiperacillin-tazobactam(4.5grthree times a day) plus vancomicin (1gr twice a day) and oral doxycycline(100mgtwiceaday)wasimmediatelystarted.

On theseconddayof hospitalization,thepatient’s condition worsened:theskinrashbecameovertlypetechial,andthepicture of severe sepsis with multiorgan system failure worsened. Laboratoryresultswerenotdiagnosticexceptreal-timePCRassay forR.conoriisubsp.Israelensis.

RickettsialDNAwasdetectedfromfullbloodspecimenswitha highlysensitivereal-timePCRassayforthedetectionofspotted fever and typhus group rickettsiae using previously published primersandprobetotheRickettsiarickettsiicitratesynthasegene, gltA(Stenosetal.,2005).TheCSisr-Pprobe(50-FAM-TGTAATAGC AAGAATCGTAGGCTGGATG-TAMRA-30₎_was_speci_ﬁcally_designed

froma highlyconserved regionof thecitrate synthasegene to detectR.conoriisubsp.israelensisinadditiontoSFGrickettsiae.

Thepatientwastreatedwithdoxycyclineforsevendays,and fever subsided completely after three days of treatment. The patient was discharged from hospital 10days after admission, withoutanysequel.

Case2

A65-year-oldotherwisehealthyItalianwomanwas hospital-izedwitha6-dayhistoryofhighfever(40C),headache,vomiting and,four dayslater,a maculopapularrashinvolving thetrunk,

limbs,palms,andsoles.Onadmission,thepatientwasagitated, confused,dysarthricand exhibitedbilateral dysdiadochokinesis. Mildneckstiffness andpositiveKernig’ssignwerepresent.She was febrile (39C), tachycardic (100 bpm), and tachypnoeic (respiratoryrate 28 breathsperminute).A maculopapularrash coveredtheentirebodysurface,andpetechiallesionswerealso present on theankles. A brain CT scan was negative for acute ischemic-hemorrhagicevents.MRI,performedwiththesuspectof encephalitis,showedglioticoutcomesbasedonhypoxic-ischemic lesions.Laboratoryinvestigationsyieldedthefollowingresults: C-reactiveproteinlevel67mg/L,leukocytecount52109_/L,_platelet

count 73109_/L, _aspartate _{aminotransferase} ₁₇₂_U/L; _alanine

aminotransferase 289U/L, d-dimer 2264ng/mL. Routine blood andurinecultures,serologictestsandPCRforRickettsiaspp.were performed.(seeabove).Thepatientdidnotgiveconsentforthe execution of a lumbar puncture. Treatment with intravenous ceftriaxone(2gtwiceaday)plusvancomicin(1gtwiceaday)and oraldoxycycline(100mgtwicea day)wasimmediately started. Laboratoryresultswerenotdiagnosticexceptreal-timePCRassay for R. conorii subsp. israelensis. The patient was treated with doxycycline for seven days and was discharged from hospital 20daysafteradmission.Feversubsidedcompletelyafterfourdays ofhospitalization.

Literaturereviewanddiscussion

For the review of published cases, a PubMed search was performed combining the terms (israelensis OR israeli) AND (RickettsiaORRickettsiosesORConorii)withoutlimits;references werealsocheckedforrelevantarticles,includingreviewpapers.

Astudywasconsideredeligibleforinclusioninthereviewifit reportedcasesofISFdocumentedbymolecularbiologymethods. Our search retrieved69 articles;of them, 30 described human casesof probableISF(Yagupskyand Wolach,1993; Weinberger etal.,2008;Giammancoetal.,2005a;Bacellaretal.,1999;Amaro etal.,2003;DeSousaetal.,2003a;DeSousaetal.,2008;DeSousa etal.,2005;Botaetal.,2016;Znazenetal.,2011;Boillatetal.,2008; Chaietal.,2008;Znazenetal.,2013;Mokranietal.,2012;Oteoand Portillo,2012;Atiasetal.,2010;Harrusetal.,2007;Brouquietal., 2007;DeSousaetal.,2006;Giammancoetal.,2005b;DeSousa etal.,2003b;Leitneretal.,2002;Kleinetal.,1995;Eremeevaetal., 1994;Kellyetal.,1994; Manoretal.,1992;Hanukaetal.,1992; RehácekandTarasevich,1991;Wolachetal.,1989;Yagupskyand Gross, 1985) but only the 9 describing 91 patients with ISF conﬁrmed by molecular biology techniques (Weinberger et al., 2008;Giammancoetal.,2005a;Bacellaretal.,1999;Amaroetal., 2003;DeSousaetal.,2008;Botaetal.,2016;Znazenetal.,2011; Boillat et al., 2008; Chai et al., 2008) werefurther considered (Figure1).

Mostofthearticlesweresinglecasereports,buttherewasone largecaseseriesbyDeSousaetal.(DeSousaetal.,2003a;DeSousa etal.,2008).

Data regardingtheclinicalcharacteristics,therapy,diagnosis andoutcomeoftheabove91patientswithISFandourtwonew casesareshowninTable1.

Allbuttwo caseswerecontractedinthreecountries:Israel, PortugalandItaly.Onecasewasreportedinapatientreturning fromatriptoLibyaandonecaseinTunisia(Znazenetal.,2011; Boillat et al., 2008). Mean agewas 56.2 (min. max 12-76; sd 15.29).

Medical history was unremarkable in all reviewed cases reportedexceptin theﬁrstofourtwocases thathad ahistory ofchronicalcoholabuse.

Theillness hada suddenonset withfever(81%), rash(77%), headache(44%);tachenoirewaspresentin27%ofthecases,and gastrointestinalsymptomswerepresentin50%ofthecases.27.3%

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of patients died of multiorgan failure, acute renal and hepatic failure,purpurafulminansandacuteencephalitis.

Inallcases,molecularbiologytechniquesallowedthedetection of copies of rickettsial DNA with ampliﬁcation of speciﬁc sequencesofthegenesencoding16SrRNA,the17-kDaprotein, citratesynthase(gltA),andtheoutermembraneproteinsOmpA andOmpB(Znazenetal.,2013)onblood(13cases),eschar(3cases) andautopsysamples(2cases).

Serology,performedwithimmunoﬂuorescenceassay(IFA)or enzyme-linkedimmunosorbentassay(ELISA),waspositiveinonly 11%ofcases.

Inallcases,therapeuticregimensincludedintravenousororal doxycycline.

ISF does not appear to be limited to Israel, but is more widespreadintheMediterraneancountriesthanﬁrstbelieved,and casesfromItaly,Portugal,LibyaandTunisiahavebeenreported.

ThetwocasesofsevereISFwedescribedhadafavorablecourse. Case 1 experienced severe sepsis reaching new criteria for diagnosisofsepsis(Giamarellos-Bourboulisetal.,2016);hehad aprovenriskfactorfordevelopingasevereformofthedisease; analysisoftherelationshipbetweencomorbiditiesandafatalMSF outcomedemonstratedthatalcoholismisastatisticallysigniﬁcant hostconditionwhichisariskfactorforafataloutcomeandfor severityofdisease(DeSousaetal.,2008).Case2hadencephalitic symptoms but did not have risk factors like the other cases examined. Nevertheless,most examined cases of ISFpresented severeformsofthediseaseandahighfatalityratewasfound.

DeSousaetal.carriedoutaprospectivestudyon69Portuguese patientswithISFandcomparedtheclinicalpictureandseverityof R.conoriisubsp.israelensisandR.conoriisubsp.conoriiinfection. They showed a statisticallysignificantlygreater severity of ISF comparedtoMSFinfectioncausedbyR.conoriisubsp.conorii;case fatalityrateforR.conoriisubsp.israelensiswassignificantlygreater than for R. conorii subsp. conorii infection(29% vs.13%),and a greaterpercentageofpatientswithISFstraininfectionrequired admissiontoICU,comparedtothosewithR.conoriisubsp.conorii infection(36%vs22%)(DeSousaetal.,2008).Allcasesreportedin Israelhavebeenfatal,aswellasthetwocaseswhichoccurredin the UK _– a tourist traveling in Portugal and another subject probablyinfectedinLibya(Weinbergeretal.,2008;Znazenetal., 2011; Boillatet al.,2008).Amongthecases of ISFdescribed in Portugal,apartfromthecasesdescribedbyDeSousa,twoofthose reportedbyBacellardiedofshockandmultiorganfailure(Bacellar et al., 1999). Of the 7 cases described in Italy, outcome was favorableinthetwocaseswehavereportedandintwooutoffive reportedbyGiammanco;theother3patientsdeveloped dissemi-natedintravascularcoagulationandprogressiontowardcomaand oneofthesepatientsdiedthedayafteradmission(Giammanco etal.,2005a).

Therefore,R.conoriisubsp.israelensiswouldappeartobemore virulent than R. conorii subsp. conorii even if the microbial pathogenic mechanism by which it causes more severe illness remainstobedetermined.

Gastrointestinal symptoms such as nausea, vomiting, and diarrheahavebeenprominentmanifestationsreportedinpatients withfatalcourseofISFand,overall,morefrequentinpatientswith ISFcomparedwithR.conoriisubsp.conorii–infectedpatients(De Sousaetal.,2008).

Tachenoire,theblackescharatthesiteofthetickbite,inour experienceispresentinmorethan60%of casesofMSF(Cascio etal.,2001;Colombaetal.,2006;Cascioetal.,1998;Cascioetal., 2002); however, it is markedly less noted in ISF,where it was presentinonly27%ofpatients.Theabsenceofescharmaybean obstacletocorrectdiagnosisespeciallyincasesoftravelerscoming fromnon-endemicareas(Znazenetal.,2011;Boillatetal.,2008). Therefore, rickettsiosis should always be suspected in febrile travelers,especiallywhenthey presentwitha rash,eveninthe absenceofhistoryoftickexposureandinoculationeschar;patients should start appropriate therapy without delay if suspicion of rickettsiosis arises in order to prevent a poor outcome due to aggressiverickettsialstrains.Indeed,thesupposedabilityoftheISF rickettsiatocauselife-threateningdiseasehasbeenalsoascribed tolatediagnosisduetoitsuncharacteristicpresentation(Yagupsky andWolach,1993).

TetracyclinesareconsideredstandardtreatmentforMSFeven thoughttheycancausesigniﬁcantadverseeffectslikestainingof theteethandbonetoxicity,especiallyinchildren.Forthisreason themacrolideshaveemergedasapotentialalternativetherapyin children (Cascio et al., 2001; Cascio et al., 2002; Cascio and Colomba,2002).Inallreviewedcases,butone,doxycyclinewas promptlystarted;delayedmedicalconsultationandlateinitiation ofantimicrobialtherapy(6daysaftersymptomsonset)mayhave contributed to the fatal course in the UK tourist traveling in Portugal(Chaietal.,2008).Haemophagocyticlymphohistiocytosis isararebutpotentiallyfataldiseasethatcanbeassociatedwith Rickettsial infection and other zoonotic diseases (Cascio et al., 2012;Cascioetal.,2011).

Serology was positive in only 11%. Therefore, it would be advisabletouseaPCRtestthatallowsrapiddiagnosisthroughthe detectionofcopiesofrickettsialDNA(Znazenetal.,2013).Skin biopsyspecimens, particularlyeschar biopsyspecimens, canbe usedfordetectionofRickettsiaspp.bymoleculartools,butthis techniqueis invasiveand painful forpatientsand isdifﬁcultto

Figure1.Studyselection.Algorithmdepictingliteraturesearchﬂowchartandwhy studieswereincludedorexcluded.

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Table 1

Clinical characteristics, therapy and outcome of 91 ISF cases. Author/Year

(ref) (n. patients)

Country Age (years or average)

Sex Medical history

Presenting symptoms and signs Eschar,

(n) PCR (eschar/ blood/ autopsy) Serology (IFA or ELISA) Outcome Therapy Fever (n) Cutaneous (n) CNS (n) Gastrointestinal (n) Bacellar et al. (1999)(3 pts)

Portugal 71 3 F unremarkable Yes (3) Rash (2) Headache (2) Nausea (1), Vomiting (2), Epigastric pain (1)

Absent Blood (3 pts) Positive (1pt)

1 Cured, 2 Died

Oral Doxycycline plus others not speciﬁed

Amaro et al. (2003)(8 pts)

Portugal 59.3 4 M, 4 F

unremarkable Yes (8) Rash (7) Headache (5) Abdominal cramps and pain (4), Diarrhea (2), Vomiting (1), Upper gastric hemorrhage (1), Oral ulcers (1) Present (5 pts) Blood (3 pts) Positive (3 pts) 4 Cured, 4 Died NA Giammanco et al. (2005a) (5 pts) Italy 49 3 M, 2 F

unremarkable Yes (5) Rash (5) Headache (5) No Present (2 pts) Blood (5 pts) positive (4 pts) 4 Cured, 1 Died Oral Doxycycline Weinberger et al. (2008) (1 pt)

Israel 51 1 M unremarkable Yes Rash Headache No Absent autopsy

samples

Negative Died Oral doxycycline plus i.v. meropenem Chai et al. (2008)(1 pt) UK Traveler to South Portugal

63 1 F unremarkable Yes Rash Headache Diarrhea Absent autopsy

samples

Positive Died Oral doxycycline plus ciproﬂoxacin

De Sousa et al. (2008)

(69 pts)

Portugal NA NA unremarkable Yes (65) Rash (63) Headache (28) Vomiting (23), Diarrhea (17) Present (23, 38%) Blood and eschar (numbers NA) NA 49 Cured, 20 (29%) Died Doxycycline (46 pt) Doxycycline plus ﬂuoroquinolone (7 pt) Fluoroquinolone (6 pt) Boillat et al. (2008)(1 pt)

Libya 63 1 M unremarkable Yes Rash Headache Epigastric pain Absent Eschar Negative Died doxycycline plus

ceftriaxone

Znazen et al. (2011)(2 pts)

Tunisia 45, 46 2 M unremarkable Yes (2) Rash (2) Headache (2) No Absent Blood (1 pt) and eschar (2 pts) Positive (1 pt) 2 Cured NA Bota et al. (2016)(1 pt)

Portugal 12 1 F unremarkable Yes Rash Headache Vomiting Absent Blood Positive Cured Ceftriaxone, clindamycin,

plus oral doxycycline Present cases (2 pts) Italy 55 1 M, 1 F Alcoholism (1)

Yes (2) Rash (2) Headache (2), mental confusion (1), dysarthria (1), signs of meningeal irritation (1)

Vomiting (1) Absent blood Positive (2 pts)

2 Cured Doxycycline plus piperacillin-tazobactam and vancomycin C. Colomba et al. / International Journal of Infectious Diseases 61 (20 17 ) 7– 12

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performoncertain areas of thebody (Parola etal., 2013).PCR detectionfollowedbygeneticcharacterizationcandeterminethe genotypeoftheorganismtothelevelofgenus,species,andstrain, andallowsanupdateofepidemiologicalknowledge.Todate,the genomes ofallR.conorii subspecieshavebeensequenced. The draftgenomeofR.conoriisubsp.Israelensisyeldedatotalgenome of1,252,815nucleotidesinwhichnoplasmidhasbeendetected. OrthologousgenesbetweenR.conoriisubsp.israelensisandthe otherthreeR.conoriisubspecieswereidentiﬁedsuggestingthat the genomes of these bacteria werealmost perfectlysyntenic. However,somegenes,likethoseforNADHdehydrogenaseIchainB (NuoB), glycerol-3-phosphate cytidyltransferase (TagD), and MazG-like protein were not detected in the R. conorii subsp. israelensisgenome,whiletheywerepresentinthoseoftheother threeR.conoriisubspecies.Whetherthisdifferenceexplainsthe differences in clinical expression observed among subspecies remainstobedemonstrated(Cascioetal.,2011).

Inconclusion,thegeographicdistributionofISFiswiderthan previously thoughtand it is possible that severe cases of MSF describedinliteratureandbelievedtobecausedbyR.conorisubsp. conorii were instead caused by R. conorii subsp. israelensis (Colombaetal.,2014;Saporitoetal.,2010).

Conﬂictsofinterest None.

Sourcesoffunding

Therewasnotanyﬁnancialsupportforthisresearch. Ethicalapproval

Ethicalapprovalwasnotrequired. Acknowledgements

We have not received substantial contributions from non-authors.

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