Renal Involvement in Mediterranean Spotted Fever: Clinical and Histopathological Data.

OBJECTIVE: Mediterranean spotted fever (MSF) is a tick-borne rickettsial infection endemic to the Mediterranean coastline countries. As a result of growing tourism, imported cases have been registered in many nonendemic countries and regions. We present clinical laboratory parameters and histopathological data on renal impairment in patients with MSF. The study meets our goal of identifying kidney involvement and detecting renal damage in people with MSF. SUBJECTS AND METHODS: Three hundred fifty patients with MSF with a diagnosis confirmed by immunofluorescence analysis were tested for serum urea, creatinine, and albumin. Fifty-five patients with malignant form of MSF were divided into 2 groups: 19 fatalities and 36 survivors. The percentage of patients with acute renal failure (ARF) was compared in both groups. RESULTS: Subjects with elevated urea and creatinine levels increased from 5.21 to 3.47% in mild to 48.78 and 29.26% in severe MSF, respectively. Loss of serum albumin also increased from mild to severe MSF. Renal impairment comprised 60% of the cohort of 55 patients with malignant MSF: 89.4% in the group of deaths and almost twice less in the survivors. ARF developed in 84.2% of fatal cases and was >2 times less in survivors. Postmortem light microscopy of renal samples of 9 fatal cases revealed perivascular mononuclear inflammatory infiltrates, vasculitis with fibrinoid necrosis, acute tubular necrosis, interstitial edema, hemorrhage, and thrombosis. CONCLUSION: Renal pathology associated with MSF rickettsial infection consists of systemic small vessel vasculitis and vascular injury, leading to ARF in the most severe cases.

[Haemophagocytic syndrome secondary to Mediterranean spotted fever]. / Syndrome d'activation macrophagique secondaire à une fièvre boutonneuse méditerranéenne.

INTRODUCTION: Haemophagocytic syndrome (HS) is a rare disease with a severe prognosis that is defined by clinical, laboratory and histopathological criteria. Infections represent the classical cause of HS. HS secondary to Mediterranean spotted fever (MSF) is rare with only a few cases being reported in the literature. OBSERVATIONS: We report two cases of HS secondary to MSF in 2 men aged 77 and 63 years presenting a febrile maculo-purpuric eruption with inoculation ulcer associated with laboratory abnormalities (cytopenia, elevated ferritin, hypertriglyceridaemia). Haemophagocytosis was present in 2 cases. Serology and PCR for Rickettsia conorii were positive and militated in favour of recent infection responsible for the diagnosis of MSF. DISCUSSION: The first case of HS was described in 1979. Sixteen cases of HS secondary to MSF are described in the literature. Cytopenia associated with hyperferritinaemia and hypertriglyceridaemia strongly suggests MSF complicated by HS. The prognosis depends on the time elapsed since diagnosis and host-specific factors. Immunosuppressants and antibiotics may be necessary to ensure healing. CONCLUSION: Rickettsioses can induce HS, and this potential complication with a severe prognosis must be known.

Rickettsia massiliae infection and SENLAT syndrome in Romania.

The purpose of this prospective study is to describe the clinical and epidemiological characteristics of rickettsioses in Romania, where only Rickettsia conorii is known by clinicians but new Rickettsia species have been identified recently in ticks. A total of eight patients, including a nine-year-old child, were included between June 2011 and June 2012, in the Hospital for Infectious and Tropical Diseases, Bucharest, Romania. Seven cases presented during summer months and one in spring. Six patients presented a generalized rash with fever, myalgia and skin eschar. The last two patients presented a typical SENLAT syndrome, characterized by scalp eschar and neck lymphadenopathy. Using serological tools, we confirmed for the first time two cases of Rickettsia massiliae, the agent of spotted fever disease, and one case of Rickettsia slovaca, and one case of R. slovacaRickettsia raoultii the agents of SENLAT syndrome.

Shell-vial culture, coupled with real-time PCR, applied to Rickettsia conorii and Rickettsia massiliae-Bar29 detection, improving the diagnosis of the Mediterranean spotted fever.

Rickettsia conorii and Rickettsia massiliae-Bar29 are related to Mediterranean spotted fever (MSF). They are intracellular microorganisms. The Shell-vial culture assay (SV) improved Rickettsia culture but it still has some limitations: blood usually contains low amount of microorganisms and the samples that contain the highest amount of them are non-sterile. The objectives of this study were to optimize SV culture conditions and monitoring methods and to establish antibiotic concentrations useful for non-sterile samples. 12 SVs were inoculated with each microorganism, incubated at different temperatures and monitored by classical methods and real-time PCR. R. conorii was detected by all methods at all temperatures since 7th day of incubation. R. massiliae-Bar29 was firstly observed at 28°C. Real-time PCR allowed to detected it 2-7 days earlier (depend on temperature) than classical methods. Antibiotics concentration needed for the isolation of these Rickettsia species from non-sterile samples was determined inoculating SV with R. conorii, R. massiliae-Bar29, biopsy or tick, incubating them with different dilutions of antibiotics and monitoring them weekly. To sum up, if a MSF diagnosis is suspected, SV should be incubated at both 28°C and 32°C for 1-3 weeks and monitored by a sensitive real-time PCR. If the sample is non-sterile the panel of antibiotics tested can be added.

Parinaud's oculoglandular syndrome revealing subclinical Rickettsia conorii infection.

The purpose of this study was to report a case of Parinaud's oculoglandular syndrome associated with subclinical Rickettsia conorii infection. We report a case of a 66-year-old male patient presented with unilateral persistent granulomatous conjunctivitis in the left eye and an ipsilateral preauricular lymphadenopathy without associated systemic features. Laboratory evaluation showed a positive indirect immunofluorescence antibody test for R. conorii. The patient received a 2-week course of oral doxycycline, with subsequent complete resolution of all his symptoms. Rickettsial disease should be considered in the differential diagnosis of oculoglandular syndrome with or without associated systemic symptoms in any patient living in or returning from a specific endemic area.

Skin lesions and inoculation eschars at the tick bite site in spotted fever group rickettsioses: experience from a patient series in eastern crete, Greece.

The main clinical signs and symptoms caused by a rickettsial infection typically begin 6-10 days after the bite and are accompanied by nonspecific findings such as fever, headache and muscle pain. The diagnosis is mainly based on serological tests, however antibody presentation may be delayed, at least at the early stages of the disease, while seroconversion is usually detected 10-15 days after disease onset. Culture is difficult, requires optimized facilities and often proves negative. Under this scope, the presence of a characteristic inoculation eschar at the bite site may prove a useful clinical tool towards the early suspicion and diagnosis/differential diagnosis of tick-borne rickettsioses, even before the onset of rash and fever or serological confirmation. We describe herein the presence of skin lesions and/or an inoculation eschar at the tick bite site in 17 patients diagnosed, by molecular means, as suffering from spotted fever group rickettsioses. The detection of the pathogen's DNA in biopsy samples proved to be a useful means for early rickettsiae detection and identification. Moreover, the presence of an infiltrated erythema always seemed to precede the appearance of an eschar by 2-5 days and the initiation of fever by 1-10 days; these two signs might also prove useful in the context of the final diagnosis.

Mediterranean spotted fever in the Trakya region of Turkey.

Mediterranean spotted fever (MSF) is caused by a tick-borne pathogen, Rickettsia conorii subsp. conorii, belonging to the spotted fever group (SFG) rickettsiae. The aim of the present study was to evaluate the cases with confirmed diagnosis of MSF from 2003 to 2009 in the Trakya region of Turkey. Patients with high fever, maculopapular rash (involving the palms or soles) and/or a black inoculation eschar at the site of the tick bite (tache noire) were included in the study. Before doxycycline treatment, skin biopsy specimens, preferably from the eschar or from the maculopapular rash, were obtained for DNA extraction. Immunofluorescence assay (IFA) was performed to detect IgM and IgG antibodies against R. conorii in acute and convalescent sera. Afterwards, a standard PCR reaction using primers suitable for hybridisation within the conserved region of genes coding for outer membrane protein A (ompA) and citrate synthase (gltA) and DNA sequencing were performed. There were 128 patients with confirmed MSF diagnosis. Using IFA, seroconversion or a fourfold or greater rise in titre was observed in 97 (77%) patients, whereas a single high titre was demonstrated in 16 (12.7%) patients. According to PCR analysis, 77 (72.6%) of 106 biopsy samples showed positive results. Of these, 58 (73%) of 79 biopsy specimens were from the eschar and 19 (70%) of 27 specimens were from the maculopapular rash. No significant difference was found between the rate of positive skin biopsies taken from the eschar and the maculopapular rash. DNA sequence analysis was performed to all PCR-positive cases, and R. conorii conorii (type strain: Malish, ATCC VR-613) was detected in each of them. MSF is prevalent, but has been underdiagnosed and underreported so far in Turkey. It is a potentially severe and even fatal disease resembling viral haemorrhagic fevers that has to be included in the differential diagnosis of febrile illness associated with thrombocytopenia, even in the absence of an eschar or a tick bite. While IFA allows for retrospective diagnosis in MSF, advanced molecular techniques provide the rapid detection of rickettsia in all skin samples, including eschar and maculopapular rash.

Contribution of NK cells to the innate phase of host protection against an intracellular bacterium targeting systemic endothelium.

We investigated the mechanisms by which natural killer (NK) cells mediate innate host defense against infection with an endothelium-targeting intracellular bacterium, Rickettsia. We found that a robust Rickettsia-induced innate response in resistant mice cleared the bacteria early in the infection and was associated with significantly higher frequencies of splenic interferon (IFN)-γ (+) CD8(+) T cells and cytotoxic NK cells compared with susceptible mice. More importantly, NK cell-deficient Rag(-/-)γc(-/-) animals displayed significantly increased susceptibility to Rickettsia infection compared with NK cell-sufficient Rag(-/-) mice, as evidenced by impaired bacterial clearance, early development of severe thrombosis in the liver, and a decreased serum level of IFN-γ. Furthermore, the lack of NK cells also impaired host resistance of CB-17 scid mice to Rickettsia, similar to what was observed in Rag(-/-)γc(-/-) mice. Interestingly, perforin deficiency in Rag(-/-)Prf1(-/-) mice resulted in greater thrombosis and insignificantly different systemic levels of IFN-γ compared with Rag(-/-) mice, suggesting that perforin, which is mainly produced by NK cells, is involved in the prevention of vascular damage. Together, these findings reveal that NK cells mediate the innate phase of host protection against infection with rickettsiae, most likely via IFN-γ production. Furthermore, NK cells are involved in preventing rickettsial infection-induced endothelial cell damage, possibly via perforin production.

Fatal Mediterranean spotted fever in Greece.

Forty-five days after the first confirmed and fatal Crimean-Congo haemorrhagic fever (CCHF) case in Greece in 2008, a female patient with similar signs and symptoms (high fever, thrombocytopaenia) and resident of the same area, was admitted to the University General Hospital of Alexandroupolis. Before admission, she had visited a local hospital where a cephalosporin was prescribed. A rash manifested over subsequent days, which was misdiagnosed as an allergy to the drug. Upon admission to the University Hospital, she was given further antibiotics, including doxycycline; a few hours later, ribavirin was added because CCHF was suspected. After the patient's death, rickettsiosis caused by Rickettsia conorii conorii (Meditteranean spotted fever; MSF) was diagnosed. Extremely high values of interleukin (IL)-1ra, IL-6, interferon-gamma-inducible protein-10, monocyte chemoattractant protein-1 and an absence of tumour necrosis factor-alpha were observed. MSF is a potentially severe and even fatal disease resembling viral haemorrhagic fevers that has to be included in the differential diagnosis of febrile syndromes combined with thrombocytopaenia, even when a tick bite is not reported, and an eschar is absent. Physicians have to be aware of MSF in patients with severe disease who are returning from the Mediterranean area.

Unusual pancytopenia secondary to haemophagocytosis syndrome in rickettsioses.

We report two patients who presented with a long-lasting febrile illness associated with pancytopenia. Both of them had evidence of hypercellular marrow with haemophagocytosis. They were confirmed as having rickettsial infections by serology and had a rapid haematological recovery with anti-rickettsial antibiotics. We highlight the importance of considering rickettsial infections in patients with such clinical presentations, especially in areas where these infections are endemic or re-emerging. Empirical use of anti-rickettsial antibiotics in such situations could be beneficial, when facilities to diagnose rickettsial diseases are not readily available.

Evidencia clínica y serológica de rickettsiosis canina en Chile / Clinical and serological evidence of canine rickettsiosis in Chile

En Chile, no se han documentado infecciones por Rickettsias en mascotas; algunas de ellas tienen importante potencial zoonótico. Objetivos: Reportar dos casos de rickettsiosis canina con confirmación serológica y determinar seroprevalencia de Rickettsia sp un grupo de caninos. Métodos: IgG anti-Rickettsia conorii y anti-Anaplasma phagocitophilum por IFI en dos caninos con cuadro clínico sugerente de rickettsiosis. Determinación de IgG anti-R. conorii en 77 caninos. Resultados: Como casos clínicos hubo un canino con fiebre, mialgias y melena y otro con manifestaciones he-morrágicas y compromiso neurológico. Seroprevalencia: 35% de los caninos presentaban IgG anti-Rickettsia. Discusión: Se reporta por primera vez en Chile la presencia de rickettsiosis canina, tanto clínica como serológica. Se documenta co-infección por Rickettsia y Anaplasma, dos agentes transmitidos por garrapatas. Es necesario realizar estudios de biología molecular para confirmar la especie de rickettsia presente en Chile. Además, debe estudiarse el rol zoonótico de estas infecciones en nuestro medio.

Rickettsial infections in pets have not been documented in Chile. Some of those infections have relevant zoonotic potential. Objectives: To report two serologically confirmed cases of canine rickettsiosis. To determine seroprevalence to Rickettsia sp in a group of dogs. Methods: IgG antibodies anti-R. conorii and anti-A. phagocitophilum by IFI in two dogs with clinical rickettsiosis. IgG antibodies anti-R. conorii in a group of 77 dogs. Results: Clinical cases: a dog presented with fever, myalgias and melena, another dog with bleeding and neurological involvement. Seroprevalence: 35% of the dogs had antibodies against Rickettsia. Discussion: This is the first evidence of canine rickettsiosis in Chile, both clinical and serological. Co-infection with two tickborne agents: Rickettsia and Anaplasma, is documented. Molecular studies are needed to confirm the rickettsial species present in Chile. The zoonotic role of these infections must be also studied.

[Emerging rickettsioses]. / Rickettsiosi emergenti.

Ticks are known to carry and transmit a number of microbial agents that cause diseases in humans and animals. Among these are members of the order Rickettsiales (alpha-proteobacteria), which include the genera Rickettsia and Ehrlichia. The most common and well-known Rickettsial human disease in Europe is Mediterranean Spotted Fever (MSF), caused by Rickettsia conorii. In recent years, a number of new Rickettsia species have been discovered in Europe, some of which have been shown to be pathogenic to humans. These discoveries have been facilitated by use of sequence-based molecular identification techniques. In Italy, it is generally believed that R. conorii is the only Rickettsia species present, and clinical tests for MSF rely on antigens raised against this bacterium. We are currently undertaking a molecular screening study of Rickettsiales-bacteria in ticks from various regions of Italy, to check for the potential presence of species from this order recently discovered in other parts of Europe. So far, we have identified a number of additional species in ticks collected from northern, central and southern regions. These include the known pathogens R. helvetica and R. slovaca as well as two species which may or may not be of medical relevance: R. monacensis and R. sp. IRS4. As a part of this survey, we have identified a novel alphaproteobacterium from the medically important tick Ixodes ricinus. This bacterium, tentatively named IricES1, has the unusual property of existing within the mitochondria, as well as the cytoplasm, of ovarian cells. To our knowledge, this is the only known example of a bacterium that is able to enter the mitochondria of animals. Our recently published electron microscopic data indicates that the bacterium enters mitochondria between the inner and outer membranes, and then proceeds to consume the inner mitochondrial matrix. We will present further data on this bacterium, including: 1) its phylogenetic position based on various molecular sequences, 2) its localization within the tick based on in situ hybridization; 3) its distribution among tick populations in Europe; 4) preliminary data on attempts at culturing this bacterium in a variety of cell types. Possible interactions between the bacterium and its host will be discussed. Ticks are known to carry and transmit a number of microbial agents that cause diseases in humans and animals. Among these are members of the order Rickettsiales (alpha-proteobacteria), which include the genera Rickettsia and Ehrlichia. The most common and well-known Rickettsial human disease in Europe is Mediterranean Spotted Fever (MSF), caused by Rickettsia conorii. In recent years, a number of new Rickettsia species have been discovered in Europe, some of which have been shown to be pathogenic to humans. These discoveries have been facilitated by use of sequence-based molecular identification techniques. In Italy, it is generally believed that R. conorii is the only Rickettsia species present, and clinical tests for MSF rely on antigens raised against this bacterium. We are currently undertaking a molecular screening study of Rickettsiales-bacteria in ticks from various regions of Italy, to check for the potential presence of species from this order recently discovered in other parts of Europe. So far, we have identified a number of additional species in ticks collected from northern, central and southern regions. These include the known pathogens R. helvetica and R. slovaca as well as two species which may or may not be of medical relevance: R. monacensis and R. sp. IRS4. As a part of this survey, we have identified a novel alphaproteobacterium from the medically important tick Ixodes ricinus. This bacterium, tentatively named IricES1, has the unusual property of existing within the mitochondria, as well as the cytoplasm, of ovarian cells. To our knowledge, this is the only known example of a bacterium that is able to enter the mitochondria of animals. Our recently published electron microscopic data indicates that the bacterium enters mitochondria between the inner and outer membranes, and then proceeds to consume the inner mitochondrial matrix. We will present further data on this bacterium, including: 1) its phylogenetic position based on various molecular sequences, 2) its localization within the tick based on in situ hybridization; 3) its distribution among tick populations in Europe; 4) preliminary data on attempts at culturing this bacterium in a variety of cell types. Possible interactions between the bacterium and its host will be discussed.

Posterior segment manifestations of Rickettsia conorii infection.

PURPOSE: To characterize and analyze the posterior segment manifestations of Mediterranean spotted fever (MSF), an infectious disease caused by Rickettsia conorii. DESIGN: Prospective, noncomparative case series. PARTICIPANTS: Thirty patients (60 eyes) with serologically proven MSF at the acute stage. METHODS: Patients underwent complete ophthalmic examination, including dilated biomicroscopic fundus examination, fundus photography, and fluorescein angiography. Sequential follow-up examinations were performed in patients with evidence of posterior segment involvement. RESULTS: Of 30 patients, 25 (83.3%) had unilateral (n = 5) or bilateral (n = 20) posterior segment involvement related to MSF. Of those 25 patients, 16 (64%) had no ocular symptoms, and 9 (36%) had ocular complaints. Findings included mild vitreous inflammation (45 eyes [75%]), white retinal lesions (18 eyes [30%]), focal vascular sheathing (5 eyes [8.3%]), multiple arterial plaques (1 eye [1.7%]), intraretinal hemorrhages (14 eyes [23.3%]), white-centered retinal hemorrhages (2 eyes [3.3%]), subretinal hemorrhages (2 eyes [3.3%]), serous retinal detachment (3 eyes [5%]), macular star (2 eyes [3.3%]), cystoid macular edema (1 eye [1.7%]), optic disc edema (1 eye [1.7%]), branch retinal artery occlusion (1 eye [1.7%]), optic disc staining (30 eyes [50%]), retinal vascular leakage (27 eyes [45%]), delayed filling in a branch retinal vein (1 eye [1.7%]), and multiple hypofluorescent choroidal dots (10 eyes [16.7%]). One eye (1.7%) had retinal neovascularization at the 6-month follow-up examination. All posterior segment findings at the acute stage resolved in 3 to 10 weeks, and the final visual acuity was 20/20 in 42 of 45 affected eyes (93.3%). Retinal pigment epithelium changes developed in 9 eyes (15%), with resolved full-thickness white retinal lesions. No other abnormalities were noted in the eye with retinal neovascularization over a further follow-up of 6 months. CONCLUSION: Posterior segment involvement, frequently asymptomatic, is common in patients with acute MSF. Because the diagnosis can be easily overlooked, a careful dilated funduscopic examination, complemented by fluorescein angiography in selected cases, is recommended. Mild vitritis, retinal vasculitis, optic disc staining, white retinal lesions, retinal hemorrhages, and multiple hypofluorescent choroidal dots are the most common manifestations of MSF. Posterior segment changes in a patient with fever and/or skin rash living in or returning from a specific endemic area, especially during the spring or summer, strongly suggest R. conorii infection.

A case of pleurisy associated with antibodies to Rickettsia conorii.

Rickettsia conorii is endemic in Mediterranean area. We describe an unusual sace of R. Conorii infection, which concerns a farmer with clinical, radiological and cytological findings of pleurisy without evidence of malignancy. An elevated antibody titre for R. Conorii was observed, using an indirect immunofluorescent antibody test. After treatment with Doxycycline, the patient presented a significant improvement of his clinical and radiological image and a four-fold decrease of the antibody titre for R. conorii.