Borrelia turicatae from Ticks in Peridomestic Setting, Camayeca, Mexico.

We conducted surveillance studies in Sinaloa, Mexico, to determine the circulation of tick-borne relapsing fever spirochetes. We collected argasid ticks from a home in the village of Camayeca and isolated spirochetes. Genomic analysis indicated that Borrelia turicatae infection is a threat to those living in resource-limited settings.

Tick-borne infections in children in North America.

PURPOSE OF REVIEW: Because both incidence and awareness of tick-borne infections is increasing, review of major infections and recent advances related to their diagnosis and management is important. RECENT FINDINGS: A new algorithm, termed modified two-tier testing, for testing for antibodies to Borrelia burgdorferi , the cause of Lyme disease, has been approved and may replace traditional two-tier testing. In addition, doxycycline is now acceptable to use for treatment of and/or prophylaxis for Lyme disease for up to 21 days in children of any age. Borrelia miyamotoi , a bacterium in the relapsing fever type of Borrelia, is the first of this type of Borrelia that is transmitted by hard-bodied ticks such as Ixodes scapularis. SUMMARY: Awareness of these infections and advances in their diagnosis and treatment is important to assure the best outcomes for affected patients. Table 1 contains a summary of infections discussed.

Experimental transmission of a novel relapsing fever group Borrelia harbored by Ornithodoros octodontus (Ixodida: Argasidae) in Chile.

Tick-borne relapsing fever spirochetes of genus Borrelia thrive in enzootic cycles involving Ornithodoros spp. (Argasidae) mainly, and rodents. The isolation of these spirochetes usually involves a murine model in which ticks are fed and the spirochetes detected in blood several days later. Such an experiment also demonstrates that a given species of tick is competent in the transmission of the bacteria. Here, soft ticks Ornithodoros octodontus were collected in Northern Chile with the objective to experimentally determine its capacity to transmit a Borrelia sp. detected in a previous study. Two Guinea pigs (Cavia porcellus) were used to feed nymphs and adults of O. octodontus and the spirochetes in blood were inspected by dark-field microscopy and nested PCR. Although spirochetes were not seen in blood, DNA was detected in only one animal 11 days after the ticks were fed. Genetic sequences of Borrelia flaB, clpX, pepX, recG, rplB, and uvrA genes retrieved from DNA extraction of positive blood were employed to construct two phylogenetic analyses. On the one hand, the flaB tree showed the Borrelia sp. transmitted by O. octodontus clustering with Borrelia sp. Alcohuaz, which was previously detected in that same tick species. On the other hand, concatenated clpX-pepX-recG-rplB-uvrA demonstrated that the characterized spirochete branches together with "Candidatus Borrelia caatinga", a recently discovered species from Brazil. Based on the genetic profile presented in this study, the name "Candidatus Borrelia octodonta" is proposed for the species transmitted by O. octodontus. The fact that spirochetes were not observed in blood of guinea pigs, may reflect the occurrence of low spirochetemia, which could be explained because the susceptibility of infection varies depending on the rodent species that is used in experimental models. Although the vertebrate reservoir of "Ca. Borrelia octodonta" is still unknown, Octodon degus, a rodent species that is commonly parasitized by O. octodontus, should be a future target to elucidate this issue.

Recombinant protein immunoblots for differential diagnosis of tick-borne relapsing fever and Lyme disease.

Lyme disease (LD) is caused by a group of tick-borne bacteria of the genus Borrelia termed Lyme disease Borreliae (LDB). The detection of serum antibodies to specific LDB antigens is widely used to support diagnosis of LD. Recent findings highlight a need for serological tests that can differentiate LD from tick-borne relapsing fever (TBRF) caused by a separate group of Borrelia species termed relapsing fever Borreliae. This is because LD and TBRF share some clinical symptoms and can occur in overlapping locations. The development of serological tests for TBRF is at an early stage compared with LD. This article reviews the application of line immunoblots (IBs), where recombinant proteins applied as lines on nitrocellulose membrane strips are used to detect antibodies in patient sera, for the diagnosis and differentiation of LD and TBRF.

The global distribution and the risk prediction of relapsing fever group Borrelia: a data review with modelling analysis.

BACKGROUND: The recent discovery of emerging relapsing fever group Borrelia (RFGB) species, such as Borrelia miyamotoi, poses a growing threat to public health. However, the global distribution and associated risk burden of these species remain uncertain. We aimed to map the diversity, distribution, and potential infection risk of RFGB. METHODS: We searched PubMed, Web of Science, GenBank, CNKI, and eLibrary from Jan 1, 1874, to Dec 31, 2022, for published articles without language restriction to extract distribution data for RFGB detection in vectors, animals, and humans, and clinical information about human patients. Only articles documenting RFGB infection events were included in this study, and data for RFGB detection in vectors, animals, or humans were composed into a dataset. We used three machine learning algorithms (boosted regression trees, random forest, and least absolute shrinkage and selection operator logistic regression) to assess the environmental, ecoclimatic, biological, and socioeconomic factors associated with the occurrence of four major RFGB species: Borrelia miyamotoi, Borrelia lonestari, Borrelia crocidurae, and Borrelia hermsii; and mapped their worldwide risk level. FINDINGS: We retrieved 13 959 unique studies, among which 697 met the selection criteria and were used for data extraction. 29 RFGB species have been recorded worldwide, of which 27 have been identified from 63 tick species, 12 from 61 wild animals, and ten from domestic animals. 16 RFGB species caused human infection, with a cumulative count of 26 583 cases reported from Jan 1, 1874, to Dec 31, 2022. Borrelia recurrentis (17 084 cases) and Borrelia persica (2045 cases) accounted for the highest proportion of human infection. B miyamotoi showed the widest distribution among all RFGB, with a predicted environmentally suitable area of 6·92 million km2, followed by B lonestari (1·69 million km2), B crocidurae (1·67 million km2), and B hermsii (1·48 million km2). The habitat suitability index of vector ticks and climatic factors, such as the annual mean temperature, have the most significant effect among all predictive models for the geographical distribution of the four major RFGB species. INTERPRETATION: The predicted high-risk regions are considerably larger than in previous reports. Identification, surveillance, and diagnosis of RFGB infections should be prioritised in high-risk areas, especially within low-income regions. FUNDING: National Key Research and Development Program of China.

Serological evidence of louse-borne relapsing fever in northern Kenya.

BACKGROUND: Tick- and louse-borne relapsing fever are highly-neglected, vector-borne diseases caused by diverse Borrelia species. Presently, there are no data available on the endemicity of tick- and louse-borne relapsing fever spirochetes in Kenya. Here, we present data of a retrospective study on the seroprevalence of louse-borne relapsing fever (LBRF) in northern Kenya. METHODS: A novel immunoassay, recently established for the diagnosis of LBRF was utilized to screen 2005 blood samples collected from individuals with fever without a source in Turkana County, Kenya between May 2009 and November 2010 for anti-LBRF antibodies. RESULTS: Out of the 2005 sera analyzed, 287 samples (14.3 %) were considered anti-LBRF IgG positive. Subsequent analyses revealed that 87 out of 152 sera randomly selected from these 2005 samples were tested positive (57.2 %) for anti-LBRF IgM antibodies. Most of the IgG and IgM positive samples were from individuals living in northern regions of Turkana County. CONCLUSION: Our serological finding provides strong evidence for the occurrence of LBRF in Kenya.

Borrelia miyamotoi BipA-like protein, BipM, is a candidate serodiagnostic antigen distinguishing between Lyme disease and relapsing fever Borrelia infections.

A Borrelia miyamotoi gene with partial homology to bipA of relapsing fever spirochetes Borrelia hermsii and Borrelia turicatae was identified by a GenBank basic alignment search analysis. We hypothesized that this gene product may be an immunogenic antigen as described for other relapsing fever Borrelia (RFB) and could serve as a serological marker for B. miyamotoi infections. The B. miyamotoi gene was a truncated version about half the size of the B. hermsii and B. turicatae bipA with a coding sequence of 894 base pairs. The gene product had a calculated molecular size of 32.7 kDa (including the signal peptide). Amino acid alignments with B. hermsii and B. turicatae BipA proteins and with other B. miyamotoi isolates showed conservation at the carboxyl end. We cloned the B. miyamotoi bipA-like gene (herein named bipM) and generated recombinant protein for serological characterization and for antiserum production. Protease protection analysis demonstrated that BipM was surface exposed. Serologic analyses using anti-B. miyamotoi serum samples from tick bite-infected and needle inoculated mice showed 94 % positivity against BipM. The 4 BipM negative serum samples were blotted against another B. miyamotoi antigen, BmaA, and two of them were seropositive resulting in 97 % positivity with both antigens. Serum samples from B. burgdorferi sensu stricto (s.s.)-infected mice were non-reactive against rBipM by immunoblot. Serum samples from Lyme disease patients were also serologically negative against BipM except for 1 sample which may have indicated a possible co-infection. A recently published study demonstrated that B. miyamotoi BipM was non-reactive against serum samples from B. hermsii, Borrelia parkeri, and B. turicatae infected animals. These results show that BipM has potential for a B. miyamotoi-infection specific and sensitive serodiagnostic to differentiate between Lyme disease and various RFB infections.

Development and validation of systems for genetic manipulation of the Old World tick-borne relapsing fever spirochete, Borrelia duttonii.

Relapsing fever (RF), a vector-borne disease caused by Borrelia spp., is characterized by recurring febrile episodes due to repeated bouts of bacteremia. RF spirochetes can be geographically and phylogenetically divided into two distinct groups; Old World RF Borrelia (found in Africa, Asia, and Europe) and New World RF Borrelia (found in the Americas). While RF is a rarely reported disease in the Americas, RF is prevalent in endemic parts of Africa. Despite phylogenetic differences between Old World and New World RF Borrelia and higher incidence of disease associated with Old World RF spirochete infection, genetic manipulation has only been described in New World RF bacteria. Herein, we report the generation of genetic tools for use in the Old World RF spirochete, Borrelia duttonii. We describe methods for transformation and establish shuttle vector- and integration-based approaches for genetic complementation, creating green fluorescent protein (gfp)-expressing B. duttonii strains as a proof of principle. Allelic exchange mutagenesis was also used to inactivate a homolog of the Borrelia burgdorferi p66 gene, which encodes an important virulence factor, in B. duttonii and demonstrate that this mutant was attenuated in a murine model of RF. Finally, the B. duttonii p66 mutant was complemented using shuttle vector- and cis integration-based approaches. As expected, complemented p66 mutant strains were fully infectious, confirming that P66 is required for optimal mammalian infection. The genetic tools and techniques reported herein represent an important advancement in the study of RF Borrelia that allows for future characterization of virulence determinants and colonization factors important for the enzootic cycle of Old World RF spirochetes.

Statewide surveillance of Ixodes scapularis (Acari: Ixodidae) for the presence of the human pathogen Borrelia miyamotoi (Spirochaetales: Spirochaetaceae), a relapsing fever spirochete in Pennsylvania, USA, 2019-2020.

Borrelia miyamotoi disease is an emerging tick-borne human illness in the United States caused by Borrelia miyamotoi (Spirochaetales: Spirochaetaceae) bacterium. With Pennsylvania reporting thousands of tick-borne disease cases annually, determining the minimum infection rate (MIR) of B. miyamotoi in Ixodes scapularis (Say, Acari: Ixodidae) adults within Pennsylvania is of utmost importance. Active surveillance was performed from October 2019 to April 2020 to collect a minimum of 50 I. scapularis ticks from every county within Pennsylvania and then screened for B. miyamotoi via qPCR. Ticks were collected from all 67 counties with the majority of those being adult I. scapularis. Additional ticks collected were Dermacentor albipictus (Packard, Acari: Ixodidae), Haemaphysalis longicornis (Neumann, Acari: Ixodidae), and immature I. scapularis. Adult I. scapularis were pooled and tested for B. miyamotoi. MIR for positive B. miyamotoi pools and density of infected adult I. scapularis varied by county, with positive pools from 38 Pennsylvania counties. This is the first statewide evaluation of B. miyamotoi in Pennsylvania in questing adult I. scapularis. These prevalence and distribution data will aid health care practitioners within the state of Pennsylvania and the northeast United States to understand potential risk and bring awareness to the lesser known human Borrelia illness, Borrelia miyamotoi disease.

Borrelia nietonii sp. nov.: Relapsing Fever Spirochetes Transmitted By the Tick Ornithodoros hermsi Designated Previously as Borrelia hermsii Genomic Group II.

Background: The taxonomic status of the relapsing fever spirochete Borrelia hermsii in western North America was established in 1942 and based solely on its specific association with the soft tick vector Ornithodoros hermsi. Multilocus sequence typing (MLST) of the 16S rRNA, flaB, gyrB, glpQ, and 16S-23S rRNA intergenic spacer of B. hermsii isolates collected over many years from various geographic locations and biological sources identified two distinct clades designated previously as B. hermsii Genomic Group I (GGI) and Genomic Group II (GGII). To better assess the taxonomic relationship of these two genomic groups to each other and other species of Borrelia, DNA sequences of the entire linear chromosome were determined. Materials and Methods: Genomic DNA samples were prepared from 11 spirochete isolates grown in Barbour-Stoenner-Kelly-H medium. From these preparations, DNA sequences of the entire linear chromosome of two isolates of B. hermsii belonging to each genomic group and seven additional species were determined. Results: Chromosomal sequences of four isolates of B. hermsii contained 919,212 to 922,307 base pairs. DNA sequence identities between the two genomic groups of B. hermsii were 95.86-95.99%, which were more divergent than chromosomal sequences comparing Borrelia parkeri and Borrelia turicatae (97.13%), Borrelia recurrentis and Borrelia duttonii (97.07%), and Borrelia crocidurae and B. duttonii (97.09%). The 3' end of the chromosome of the two GGII isolates also contained a unique intact oppA gene absent from all other species examined. Conclusion: Previous MLST and the chromosomal sequences presented herein support the division of the B. hermsii species complex into two species, B. hermsii sensu stricto ( = GGI) and Borrelia nietonii sp. nov. ( = GGII). We name this unique relapsing fever spirochete in honor of our late friend and colleague Dr. Nathan Nieto for his outstanding contributions to our understanding of tick-borne relapsing fever.

Exploring the transcriptome of immature stages of Ornithodoros hermsi, the soft-tick vector of tick-borne relapsing fever.

Blood-feeding behavior has independently evolved in arthropods multiple times. Unlike hard ticks, soft ticks employ a rapid-feeding strategy for hematophagy, and there are comparatively limited studies on the transcriptomes of these organisms. This study investigates the soft tick Ornithodoros hermsi, conducting histopathological examinations at bitten skin sites and tick whole-body transcriptomic analyses across various developmental and feeding stages, including larvae, 1st-nymphal, and 2nd-nymphal stages. The results revealed the ability of O. hermsi to induce skin hemorrhage at the bite sites. Transcriptomic analyses identified three consistent transcriptional profiles: unfed, early-fed (6 h, 12 h, 24 h), and late-fed (5 days). The unfed profile exhibited high transcriptional activity across most of the functional classes annotated. In contrast, early-fed stages exhibited decreased expression of most functional classes, except for the unknown, which is highly expressed. Finally, transcriptional expression of most functional classes increased in the late-fed groups, resembling the baseline expression observed in the unfed groups. These findings highlight intense pre-feeding transcriptional activity in O. hermsi ticks, aligning with their rapid-feeding strategy. Moreover, besides shedding light on the temporal dynamics of key pathways during blood meal processing and tick development, this study contributes significantly to the transcriptome repertoire of a medically relevant soft tick species with relatively limited prior knowledge.

Multifunctional interaction of CihC/FbpC orthologs of relapsing fever spirochetes with host-derived proteins involved in adhesion, fibrinolysis, and complement evasion.

Introduction: Relapsing fever (RF) remains a neglected human disease that is caused by a number of diverse pathogenic Borrelia (B.) species. Characterized by high cell densities in human blood, relapsing fever spirochetes have developed plentiful strategies to avoid recognition by the host defense mechanisms. In this scenario, spirochetal lipoproteins exhibiting multifunctional binding properties in the interaction with host-derived molecules are known to play a key role in adhesion, fibrinolysis and complement activation. Methods: Binding of CihC/FbpC orthologs to different human proteins and conversion of protein-bound plasminogen to proteolytic active plasmin were examined by ELISA. To analyze the inhibitory capacity of CihC/FbpC orthologs on complement activation, a microtiter-based approach was performed. Finally, AlphaFold predictions were utilized to identified the complement-interacting residues. Results and discussion: Here, we elucidate the binding properties of CihC/FbpC-orthologs from distinct RF spirochetes including B. parkeri, B. hermsii, B. turicatae, and B. recurrentis to human fibronectin, plasminogen, and complement component C1r. All CihC/FbpC-orthologs displayed similar binding properties to fibronectin, plasminogen, and C1r, respectively. Functional studies revealed a dose dependent binding of plasminogen to all borrelial proteins and conversion to active plasmin. The proteolytic activity of plasmin was almost completely abrogated by tranexamic acid, indicating that lysine residues are involved in the interaction with this serine protease. In addition, a strong inactivation capacity toward the classical pathway could be demonstrated for the wild-type CihC/FbpC-orthologs as well as for the C-terminal CihC fragment of B. recurrentis. Pre-incubation of human serum with borrelial molecules except CihC/FbpC variants lacking the C-terminal region protected serum-susceptible Borrelia cells from complement-mediated lysis. Utilizing AlphaFold2 predictions and existing crystal structures, we mapped the putative key residues involved in C1r binding on the CihC/FbpC orthologs attempting to explain the relatively small differences in C1r binding affinity despite the substitutions of key residues. Collectively, our data advance the understanding of the multiple binding properties of structural and functional highly similar molecules of relapsing fever spirochetes proposed to be involved in pathogenesis and virulence.

[Progress in research of epidemiology of relapsing fever and prevention and control measures].

Relapsing fever, caused by Borreliae of the relapsing fever groups, is an infectious disease, which would cause spirochaetaemia and repeated fever in human. To comprehensively understand the classification and distribution of relapsing fever, as well as correlated factors, this paper summarizes the progress in research of epidemiology of relapsing fever in the world, and suggests prevention and control measures. The disease is heterogenous and can be divided into three groups according to vectors, i.e. tick-borne relapsing fever, louse-borne relapsing fever and the avian relapsing fever. Tick borne relapsing fever can be further divided into two types: soft tick transmission and hard tick transmission. Soft tick-borne relapsing fever generally has obvious geographical distribution characteristics, while hard tick-borne relapsing fever is widely distributed all over the world. Louse-borne relapsing fever, also known as epidemic forms of relapsing fever, is caused by body lice, and the incidence is usually associated with war, famine, refugees and poor sanitation. The prevention and control of relapsing fever should be based on local conditions.

Case report: Kikuchi-Fujimoto disease: unveiling a case of recurrent fever and enlarged cervical lymph nodes in a young female patient with a literature review of the immune mechanism.

The inflammatory response to viral infection is an important component of the antiviral response, a process that involves the activation and proliferation of CD8+ T, CD4+ T, and dendritic cells; thus, viral infection disrupts the immune homeostasis of the organism, leading to an increased release of inflammatory factors. Kikuchi-Fujimoto disease (KFD) is an inflammatory self-limited disorder of unknown etiology, and it is generally believed that the pathogenesis of this disease includes two aspects: viral infection and autoimmune response. Various immune cells, such as CD8+ T lymphocytes, CD4+ T lymphocytes, and CD123+ plasmacytoid dendritic cells, as well as the cytokines they induce and secrete, such as interferons, interleukins, and tumor necrosis factors, play a crucial role in the pathogenesis of KFD. In this article, we present a case study of a young female patient from China who exhibited typical symptoms of lymph node inflammation and fever. The diagnosis of KFD was confirmed through a lymph node biopsy. She presented with elevated ESR, IL-6, and IFN-γ. Viral markers showed elevated IgG and IgM of cytomegalovirus (CMV) and elevated IgG of Epstein-Barr virus (EBV), while changes occurred in the CD4+ T and CD8+ T cell counts. Eventually, the patient achieved disease relief through steroid treatment. Based on these findings, we conducted a comprehensive review of the involvement of viral infection-induced inflammatory response processes and autoimmunity in the pathogenesis of Kikuchi-Fujimoto disease.

Apresentação atípica de síndrome de hiper-IgM ligada ao X simulando doença inflamatória intestinal / Atypical presentation of X-linked hyper-IgM syndrome simulating inflammatory bowel disease

Relatamos o caso de um paciente do sexo masculino, que iniciou quadro de úlceras em trato gastrointestinal, associado a febre recorrente e diarreia com muco e sangue aos 10 meses de vida, suspeitado inicialmente de doença inflamatória intestinal, no entanto, não apresentou melhora do quadro com terapia imunossupressora, sendo realizada investigação para erro inato da imunidade. Nos exames laboratoriais, apresentou níveis baixos de IgG e IgA e níveis elevados de IgM e neutropenia persistente. Diante disso, foi realizado teste genético que confirmou diagnóstico de síndrome de hiper-IgM ligada ao X. Os erros inatos da imunidade podem se manifestar com doenças do trato gastrointestinal, de forma relativamente frequente, devendo entrar como diagnóstico diferencial de diarreia crônica. Inclusa nesse grupo de doenças, as síndromes de hiper-IgM constituem um grupo heterogêneo de doenças, possuindo em comum níveis significativamente baixos ou ausentes de IgG e IgA e níveis normais ou elevados de IgM, o que predispõe a infecções e febre recorrente; além de outras alterações laboratoriais, como neutropenia, que pode estar associada a úlceras no trato gastrointestinal e proctite, simulando apresentação clínica de doença inflamatória intestinal. Para o paciente relatado, foi iniciada terapia com imunoglobulinas de forma periódica, além de antibioticoprofilaxia para infecções, evoluindo com resposta clínica satisfatória. O artigo possui objetivo principal de alertar para o diagnóstico diferencial de erros inatos da imunidade diante do quadro apresentado, visando o diagnóstico precoce e a instituição da terapia adequada.

We report the case of a male patient, who started with ulcers in the gastrointestinal tract, associated with recurrent fever and diarrhea with mucus and blood at 10 months of life, initially suspected of inflammatory bowel disease, however, he did not improve the condition with immunosuppressive therapy, being investigated for inborn error of immunity. In laboratory tests, he had low levels of IgG and IgA and high levels of IgM and persistent neutropenia. Therefore, a genetic test was performed and confirmed the diagnosis of X-linked hyper IgM syndrome. Inborn errors of immunity can manifest relatively frequently with diseases of the gastrointestinal tract, and should be included as a differential diagnosis of chronic diarrhea. Included in this group of diseases, hyper-IgM syndromes constitute a heterogeneous group of diseases, having in common significantly low or absent levels of IgG and IgA and normal or high levels of IgM, which predispose to infections and recurrent fever; in addition to other laboratory alterations, such as neutropenia, which may be associated with ulcers in the gastrointestinal tract and proctitis, simulating the clinical presentation of inflammatory bowel disease. For the reported patient, therapy with immunoglobulins was started periodically, in addition to antibiotic prophylaxis for infections, evolving with a satisfactory clinical response. The main objective of the article is to alert to the differential diagnosis of inborn errors of immunity in view of the presented condition, aiming at early diagnosis and the institution of adequate therapy.

O estado da arte das síndromes autoinflamatórias associadas à criopirina / The state of the art of cryopyrin-associated periodic syndromes

As síndromes autoinflamatórias associadas à criopirina (CAPS) compreendem um grupo espectral de doenças raras autoinflamatórias. Todas estas doenças estão relacionadas ao inflamassoma NLRP3, sendo que de 50-60% dos pacientes apresentam mutações ao longo do gene NLRP3. Clinicamente, febre recorrente associada à urticária neutrofílica e outros sintomas sistêmicos são o grande marco clínico, comum a todo o espectro. O bloqueio da interleucina-1 trouxe grande alívio ao tratamento destas desordens, mas variações na resposta clínica podem ser observadas, principalmente nos espectros mais graves. Neste trabalho os autores trazem uma revisão do estado da arte das doenças autoinflamatórias CAPS. Foi realizado levantamento de literatura e, ao final, 49 artigos restaram como base para construção do texto final. O trabalho traz de forma narrativa os principais pontos relacionados a imunofisiopatologia, manifestação clínica, diagnóstico, tratamento, complicações e novas armas diagnósticas, e terapia gênica.

Cryopyrin-associated periodic syndromes (CAPS) comprise a spectrum of rare autoinflammatory disorders. They are all related to the NLRP3 inflammasome, and 50-60% of the patients harbor mutations along the NLRP3 gene. Clinically, recurrent fever associated with neutrophilic urticaria and other systemic symptoms are a hallmark of all the disorders in the spectrum. Biologic drugs that can block interleukin-1 were a milestone for the treatment of such rare diseases, although variability in clinical response to this therapeutic intervention were observed, especially in those affected by severe phenotypes. In this paper, the authors provide a state-of-the-art review of CAPS. A literature search was performed and, finally, 49 articles remained for the construction of the final manuscript. The article presents a narrative review focused on the topics related to immune pathophysiology, clinical manifestations, diagnosis, treatment, complications and new therapeutic options, and gene therapy.

Síndrome de fiebre periódica, estomatitis aftosa, faringitis y adenitis / Periodic fever, aphthous stomatitis, pharyngitis and adenitis syndrome

Introducción: El síndrome de fiebre periódica, estomatitis aftosa, faringitis y adenitis es un cuadro relativamente frecuente de curso autolimitado y buen pronóstico. Es la más común de las enfermedades autoinflamatorias que presentan fiebre recurrente y su etiología y fisiopatogenia permanecen inciertas. Objetivo: Describir el caso clínico de un niño que consultó por fiebre recurrente y faringitis y se arribó al diagnóstico de síndrome de fiebre periódica, estomatitis aftosa, faringitis y adenitis. Presentación del caso: Se trata de un paciente de 5 años que consultó por un episodio febril acompañado de faringitis y adenitis, con antecedente de múltiples episodios previos. Conclusiones: El síndrome fiebre periódica, estomatitis aftosa, faringitis y adenitis, es una entidad de curso benigno y autolimitado que constituye la causa más común de fiebre recurrente con un gran impacto en la vida de los pacientes. La fisiopatogenia permanece incierta. Es destacable la sospecha clínica para arribar al diagnóstico ya que no existen en la actualidad exámenes complementarios específicos(AU)

Introduction: Periodic fever, aphthous stomatitis, pharyngitis and adenitis syndrome is a relatively common picture of self-limiting course and good prognosis. It is the most common of self-inflammatory diseases with recurrent fever and its etiology and physiopathology remain uncertain. Objective: Describe the clinical case of a boy who was checked due recurrent fever and pharyngitis and being diagnosed with Periodic fever, aphthous stomatitis, pharyngitis and adenitis syndrome. Case presentation: This is a 5-year-old patient who was consulted due to a febrile episode accompanied by pharyngitis and adenitis, with a history of multiple previous episodes. Conclusions: Periodic fever, aphthous stomatitis, pharyngitis and adenitis syndrome is a benign, self-limiting course entity that is the most common cause of recurrent fever with a large impact on patients' lives. Its physiopathology remains uncertain. Clinical suspicion for diagnosis is noteworthy as there are currently no specific complementary test for it(AU)