A case of scrub typhus with meningitis as the onset: Case report and literature review

RATIONALE

Scrub typhus is a naturally occurring acute febrile disease caused by Orientia tsutsugamushi. Although it can cause multiple organ dysfunction, central nervous system infections are uncommon.

PATIENT CONCERNS

A 17-year-old male presented with a 5-day history of fever and headaches. The MRI of the head revealed thickness and enhancement of the left temporal lobe and tentorium cerebelli, indicating potential inflammation.

DIAGNOSES

The patient was diagnosed with a central nervous system infection.

INTERVENTIONS

Ceftriaxone and acyclovir were administered intravenously to treat the infection, reduce fever, restore acid-base balance, and manage electrolyte disorders.

OUTCOMES

Despite receiving ceftriaxone and acyclovir as infection therapy, there was no improvement. Additional multipathogen metagenomic testing indicated the presence of O tsutsugamushi infection, and an eschar was identified in the left axilla. The diagnosis was changed to scrub typhus with meningitis and the therapy was modified to intravenous doxycycline. Following a 2-day therapy, the body temperature normalized, and the fever subsided.

CONCLUSIONS

The patient was diagnosed with scrub typhus accompanied by meningitis, and doxycycline treatment was effective.

LESSION

Rarely reported cases of scrub typhus with meningitis and the lack of identifiable symptoms increase the chance of misdiagnosis or oversight. Patients with central nervous system infections presenting with fever and headache unresponsive to conventional antibacterial and antiviral treatment should be considered for scrub typhus with meningitis. Prompt multipathogen metagenomic testing is recommended to confirm the diagnosis and modify the treatment accordingly.

A Case Series on Spotted Fever and Typhus Fever Seropositivity at National Center for Disease Control and Epidemiological Perspective

Background: The rickettsioses, except for typhus fever and scrub typhus (ST), were not really recognized as distinct clinical entities until the early 20th century. Only when specific rickettsial serologic testing was introduced in the 1940s could the precise etiologies of various rickettsial diseases (RDs) be determined with certainty. Although ST is a well- recognized zoonotic disease entity, but non-scrub typhus rickettsial infection like spotted fever group and typhus group are not well studied in India and are still underestimated. Methods: We report cases who had shown seropositivity of spotted fever and typhus fever RD in IgM and IgG ELISA whose samples were referred from various hospitals of Delhi/National Capital Region in which clinicians had strong suspicion of rickettsiosis other than ST or Weil-Felix test found positive for any of the OX2, 19, and K antigens. Results: We reported 18 cases of SFG and TGRD with mostly cases presented with fever followed by hepato-intestinal symptoms. Conclusion: The vast variability and nonspecific presentation of rickettsiosis in spotted and typhus fever at times have often made it difficult to diagnose clinically. Prompt antibiotic therapy shortens the course of the disease, lowers the risk of complications, and in turn, reduces morbidity and mortality owing to RDs. There is a distinct need for physicians and health care workers at all levels of care in India to be aware of the clinical features, available diagnostic tests and their interpretation, and the therapy for these infections.

Disseminated central nervous system tuberculoma in a patient with scrub typhus: A case report

Central nervous system (CNS) tuberculosis mainly manifests as tuberculous meningitis and intracranial tuberculosis; intramedullary tuberculosis is uncommon. Scrub typhus is an acute naturally occurring infectious disease caused by Orientia tsutsugamushi. CNS tuberculoma following typhus is rare. The present study described a 60-year-old man with high fever, muscle soreness, yellowish skin and sclera and hepatosplenomegaly. At first, the patient was diagnosed with scrub typhus, after treatment with doxycycline he recovered completely. However, half a month after discharge, the patient experienced headache, night sweats and anorexia. Tuberculosis-specific enzyme-linked immunospot assay showed positive Mycobacterium tuberculosis antibody in cerebrospinal fluid (CSF). Metagenomic next-generation sequencing detected the presence of Mycobacterium tuberculosis in CSF. Magnetic resonance imaging of the brain and spinal cord showed multiple rings enhancing lesions in the cerebral hemispheres, cerebellum, brainstem and spinal cords. After the diagnosis of CNS tuberculoma, the patient was started on conventional anti-tuberculosis therapy resulting in a good prognosis.

Persistent fever in acute hepatitis: think beyond acute viral hepatitis

BACKGROUND

Acute hepatitis due to various tropical infections can mimic the clinical picture of acute viral hepatitis(AVH), leading to increased morbidity and mortality. We aimed to identify clinical and laboratory parameters that could help to distinguish acute hepatitis due to tropical infections from AVH.

METHODS

We retrospectively analyzed our database of 150 children (107 boys) with AVH and 50 children(34 boys)with acute hepatitis due to tropical infections between January 2013 and March 2023. Clinical features, investigations, complications and outcomes were compared.

RESULTS

Hepatitis A (75%) was the commonest etiology of AVH while enteric fever (34%), dengue (26%), scrub typhus (20%) and leptospirosis (16%) constituted the majority of tropical infections. Persistent fever and skin rashes were found in 88% and 16% of patients respectively in the tropical infection group and none in the AVH group (p < 0.001). On univariate analysis, prodromal symptoms, clinically detectable jaundice, cholestatic pattern, total and direct bilirubin and liver enzymes were significantly higher in AVH while headache, myalgia, leukopoenia, thrombocytopenia, hyponatremia were significantly higher in tropical infections group (all p < 0.05). Multivariate analysis identified thrombocytopenia (Odds ratio [OR] 4.237) as an independent positive predictive factor and markedly elevated total bilirubin (OR 0.575), direct bilirubin (OR 0.498), aspartate aminotransferase (OR 0.841) and alanine aminotransferase (OR 0.863) as independent negative predictive factors for acute hepatitis due to tropical infections.

CONCLUSION

High index of suspicion for tropical infections is warranted in patients with persistent fever after the onset of jaundice, especially in the presence of skin rash and thrombocytopenia.SUMMARYAcute viral hepatitis and acute hepatitis due to tropical infections can have similar clinical and biochemical parameters. Milder degree of jaundice, lower elevation of serum transaminases and thrombocytopenia can be useful predictors for acute hepatitis due to tropical infections.

First laboratory-confirmed case of scrub typhus in Shijiazhuang City, Hebei Province

Objective

Defining whether a suspected case was due to scrub typhus through laboratory testing, to understand the prevalence of scrub typhus in Shijiazhuang City, Hebei Province.

Methods

An epidemiological investigation was conducted on the suspected case, utilizing Weil-Felix test and indirect immunofluorescence assay (IFA) to detect specific antibodies against O. tsutsugamushi in serum specimens. Additionally, PCR amplification of the 56-kDa and groEL genes was performed, followed by constructing a phylogenetic tree to identify the genotype.

Results

The acute phase titer of the Weil-Felix test for the case was 1:160, which increased to 1:320 in the recovery phase. IFA assay revealed IgG titers against O. tsutsugamushi of 1:64 in the acute phase and 1:256 in the recovery phase. Sequence alignment of the PCR amplified fragment showed the highest similarity with the O. tsutsugamushi genotype. Kawasaki sequence, ranging from 99.71 to 100.00%. The strain exhibited the closest genetic relationship with the known O. tsutsugamushi Kawasaki genotype.

Conclusion

This study confirms the presence of O. tsutsugamushi in Shijiazhuang City, Hebei Province, with the identified strain belonging to the Kawasaki genotype, marking the first diagnosis of this strain in the region.

A molecular survey of zoonotic pathogens of public health importance in rodents/shrews and their ectoparasites trapped in Puducherry, India

BACKGROUND

Globally, India has a high zoonotic disease burden and lacks surveillance data in humans and animals. Rodents are known reservoirs for many zoonotic diseases and their synanthropic behavior poses a great public health threat.

METHODS

In this study, trapped rodents/shrews from randomly selected villages within Puducherry, India, and their ectoparasites were screened for zoonotic pathogens, namely, Orientia tsutsugamushi, other pathogenic rickettsiae, Leptospira spp., Cryptosporidium spp., Coxiella burnetii and methicillin-resistant Staphylococcus aureus (MRSA) using conventional PCR. A total of 58 rodents/shrews were trapped from 11 villages. The species trapped were Suncus murinus (49/58, 84.48%), Rattus rattus (8/58, 13.79%) and Rattus norvegicus (1/58, 1.72%). All ectoparasites collected were identified as mites and its infestation rate was 46.55% (27/58).

RESULTS

Real-time PCR targeting the 47 kDa gene of O. tsutsugamushi revealed positivity in one rodent and one shrew (3.45%) and two mite pools (7.41%). Conventional PCR targeting the 56 kDa gene revealed positivity in one shrew and two mite pools and the phylogenetic analysis of all three amplicons indicated the circulation of the Gilliam-related serotype. MRSA was detected in the alimentary tract of a shrew (1/32, 3.13%). Leptospira spp., Rickettsia, Cryptosporidium spp. and Co. burnetii tested negative.

CONCLUSIONS

The detection of zoonotic pathogens within reservoir hosts and vectors poses a risk of transmission to humans. This study signifies the need for zoonotic pathogen surveillance in synanthropic rodents/shrews.

mNGS helped diagnose scrub typhus-associated HLH in children: a report of two cases

Background

Scrub typhus, caused by the Orientia tsutsugamushi (Ot), is a widespread vector-borne disease transmitted by chigger mites. Hemophagocytic lymphohistiocytosis (HLH) is considered to be one of the potentially severe complications. The diagnosis of scrub typhus-associated HLH may be overlooked due to the non-specific clinical characteristics and the absence of pathognomonic eschar.

Case presentation

We obtained clinical data from two patients in the South of Sichuan, China. The first case involved a 6-year-old girl who exhibited an unexplained fever and was initially diagnosed with sepsis, HLH, and pulmonary infection. The other patient presented a more severe condition characterized by multiple organ dysfunction and was initially diagnosed with septic shock, sepsis, HLH, acute kidney injury (AKI), and pulmonary infection. At first, a specific examination for scrub typhus was not performed due to the absence of a characteristic eschar. Conventional peripheral blood cultures yielded negative results in both patients, and neither of them responded to routine antibiotics. Fortunately, the causative pathogen Orientia tsutsugamushi (Ot) was detected in the plasma samples of both patients using metagenomics next-generation sequencing (mNGS) and further confirmed by polymerase chain reaction. Subsequently, they both were treated with doxycycline and recovered quickly.

Conclusion

The unbiased mNGS provided a clinically actionable diagnosis for an uncommon pathogen-associated infectious disease that had previously evaded conventional diagnostic approaches.

Community engagement around scrub typhus in northern Thailand: a pilot project

BACKGROUND

Scrub typhus is highly endemic in northern Thailand yet awareness and knowledge are low. We developed a community engagement project to improve awareness in communities at risk of contracting scrub typhus.

METHODS

We conducted a series of engagement sessions with healthcare workers and community health volunteers so they would, in turn, engage with their communities. We evaluated our activities by assessing the increase in scrub typhus knowledge, using a series of Likert-scale items and open-ended questions. Three to 6 months after the sessions, participants were followed up to collect their experiences training community members.

RESULTS

Of 134 participants who took part in eight sessions, 87.3% were community health volunteers. Disease knowledge increased substantially after the sessions and was well maintained for up to 5 mo. Satisfaction was high and, through participant feedback, engagement materials were improved to be more useful to the communities. People with higher education had higher scores and retention.

CONCLUSIONS

Community engagement was shown to be an effective tool to develop and carry out health-promoting activities in a culturally and context-appropriate manner.

Scrub Typhus: An Acute Precipitant for Acute on Chronic Liver Failure

Acute-on-chronic liver failure (ACLF) is a clinical syndrome with high mortality. Many acute precipitating factors have been implicated in triggering the acute event of ACLF, with bacterial infections being a common precipitant. However, many other precipitants can cause ACLF; therefore, identification of these factors early in the golden window and their treatment can result in improved prognosis. Scrub typhus usually presents as uncomplicated acute febrile illness but rarely as complicated. Few case reports of scrub-typhus-induced acute liver failure have been reported but none with scrub-typhus-precipitating ACLF so far. Therefore, we are reporting a case of scrub-typhus-precipitating ACLF, where timely intervention with antibiotics results in improved outcome.

Scrub typhus in Indonesia: A cross-sectional analysis of archived fever studies samples

BACKGROUND

Scrub typhus is an understudied vector-borne bacterial infection.

METHODS

We tested archived fever samples for scrub typhus seropositivity to begin charting its geographic distribution in Indonesia. We analysed 1033 serum samples from three sites. IgM and IgG enzyme-linked immunosorbent assay (ELISA) against Orientia tsutsugamushi was performed using Karp, Kato, Gilliam, TA 716 antigens. To determine the cutoff in the absence of a presumed unexposed population and gold standard tests, we identified the visual inflection point, performed change point analysis, and used finite mixture models.

RESULTS

The optical density cutoff values used for IgM and IgG were 0.49 and 0.13, respectively. Across all sites, IgM seropositivity was 4.6% (95% CI: 3.4 to 6.0%) while IgG seropositivity was 4.4% (95% CI: 3.3 to 5.8%). The overall seropositivity across sites was 8.8% (95% CI: 8.1 to 11.7%). The overall seropositivity for Jambi, Denpasar, Tabanan were 9.7% (95% CI: 7.0 to 13.3%), 8.0% (95% CI: 5.7 to 11.0%), 9.0% (95% CI: 6.1 to 13.0%), respectively.

CONCLUSIONS

We conclude that O. tsutsugamushi exposure in humans occurred at all sites analysed and could be the cause of illness in some cases. Though it was not the main cause of acute fever in these locations, it is still important to consider scrub typhus in cases not responding to beta-lactam antibiotics. Future seroprevalence surveys and testing for scrub typhus in acute febrile illness studies will be essential to understand its distribution and burden in Indonesia.

Comparative Evaluation of Different Tissues and Molecular Techniques for the Zoonotic Surveillance of Scrub Typhus

Background and Objectives: Scrub typhus (ST) is detected in one-fourth of patients with acute febrile illnesses, confirming its nationwide re-emergence. The disease, if not diagnosed, can lead to multiple organ dysfunction and mortality. Being a vector-borne zoonotic disease, the molecular survey for pathogens in animal hosts is essential to predict the risk of its transmission to humans. Hence, this study aimed at identifying the effective animal tissue and molecular technique for zoonotic surveillance of ST infection in small animal hosts. Methods: Rodents/shrews were trapped from seventeen randomly selected villages in Puducherry between July and September, 2022. The presence of Orientia tsutsugamushi in ectoparasites and tissues including blood, lung, liver, spleen, kidney, heart, brain, and intestine retrieved from the animals was screened by nested PCR targeting 56 kDa, real-time PCR (qPCR) targeting 47 kDa and traD, and conventional PCR targeting groEL. The Weil-Felix test was carried out to detect antibodies against O. tsutsugamushi in rodent/shrew serum samples. Diagnostic accuracy measures of the molecular tests were calculated for each of the tissues by latent class modeling. Results: O. tsutsugamushi detected in the rodents/shrews were identified to be Karp-like and Kawasaki-like strains. Upon statistical analysis, qPCR targeting 47 kDa exhibited the highest accuracy measures in most of the tissues analyzed, with perfect sensitivity and specificity of 100% and 97% for intestine and lung samples for the epidemiological surveillance, respectively. Interpretation and Conclusion: The study recommends qPCR targeting 47 kDa gene and analysis of intestine and lung along with blood for the zoonotic surveillance of ST infection.

Identification of Bacteria and Viruses Associated with Patients with Acute Febrile Illness in Khon Kaen Province, Thailand

The majority of cases of undifferentiated acute febrile illness (AFI) in the tropics have an undefined etiology. In Thailand, AFI accounts for two-thirds of illnesses reported to the Ministry of Public Health. To characterize the bacterial and viral causes of these AFIs, we conducted molecular pathogen screening and serological analyses in patients who sought treatment in Chum Phae Hospital, Khon Kaen province, during the period from 2015 to 2016. Through integrated approaches, we successfully identified the etiology in 25.5% of cases, with dengue virus infection being the most common cause, noted in 17% of the study population, followed by scrub typhus in 3.8% and rickettsioses in 6.8%. Further investigations targeting viruses in patients revealed the presence of Guadeloupe mosquito virus (GMV) in four patients without other pathogen co-infections. The characterization of four complete genome sequences of GMV amplified from AFI patients showed a 93-97% nucleotide sequence identity with GMV previously reported in mosquitoes. Nucleotide substitutions resulted in amino acid differences between GMV amplified from AFI patients and mosquitoes, observed in 37 positions. However, these changes had undergone purifying selection pressure and potentially had a minimal impact on protein function. Our study suggests that the GMV strains identified in the AFI patients are relatively similar to those previously reported in mosquitoes, highlighting their potential role associated with febrile illness.

Development and implementation of a strategy for early diagnosis and management of scrub typhus: an emerging public health threat

Scrub typhus, caused by Orientia tsutsugamushi, is a re-emerging zoonotic disease in the tropics with considerable morbidity and mortality rates. This disease, which is mostly prevalent in rural areas, remains underdiagnosed and underreported because of the low index of suspicion and non-specific clinical presentation. Limited access to healthcare, diagnostics, and treatment in rural settings further makes it challenging to distinguish it from other febrile illnesses. While easily treatable, improper treatment leads to severe forms of the disease and even death. As there is no existing public health program to address scrub typhus in India, there is an urgent need to design a program and test its effectiveness for control and management of the disease. With this backdrop, this implementation research protocol has been developed for a trial in few of the endemic "pockets" of Odisha, an eastern Indian state that can be scalable to other endemic areas of the country, if found effective. The main goal of the proposed project is to include scrub typhus as a differential diagnosis of fever cases in every tier of the public health system, starting from the community level to the health system, for the early diagnosis among suspected cases and to ensure that individuals receive complete treatment. The current study aimed to describe the protocol of the proposed Scrub Typhus Control Program (STCP) in detail so that it can receive valuable views from peers which can further strengthen the attempt.

Pathological Responses in Asian House Shrews (Suncus murinus) to the Naturally Acquired Orientia tsutsugamushi Infection

Scrub typhus is a re-emerging disease caused by Orientia tsutsugamushi, transmitted by mites belonging to the family Trombiculidae. Humans and rodents acquire the infection by the bite of larval mites/chiggers. Suncus murinus, the Asian house shrew, has been reported to harbor the vector mites and has been naturally infected with O. tsutsugamushi. The present study aimed to localize and record O. tsutsugamushi in the tissues and the host response in shrews naturally infected with O. tsutsugamushi. Sheehan's modified May-Grunwald Giemsa staining was carried out in 365 tissues from 87 animals, and rickettsiae were documented in 87 tissues from 20 animals. Immunohistochemical (IHC) staining, using polyclonal antibodies raised against selected epitopes of the 56-kDa antigen, was carried out, and 81/87 tissue sections were tested positive for O. tsutsugamushi. By IHC, in addition to the endothelium, the pathogen was also demonstrated by IHC in cardiomyocytes, the bronchiolar epithelium, stroma of the lungs, hepatocytes, the bile duct epithelium, the epithelium and goblet cells of intestine, the tubular epithelium of the kidney, and splenic macrophages. Furthermore, the pathogen was confirmed by real-time PCR using blood (n = 20) and tissues (n = 81) of the IHC-positive animals. None of the blood samples and only 22 out of 81 IHC-positive tissues were tested positive by PCR. By nucleotide sequencing of the 56-kDa gene, Gilliam and Karp strains were found circulating among these animals. Although these bacterial strains are highly virulent and cause a wide range of pathological alterations, hence exploring their adaptive mechanisms of survival in shrews will be of significance. Given that the pathogen localizes in various organs following a transient bacteremia, we recommend the inclusion of tissues from the heart, lung, intestine, and kidney of reservoir animals, in addition to blood samples, for future molecular surveillance of scrub typhus.

Concatenated ScaA and TSA56 Surface Antigen Sequences Reflect Genome-Scale Phylogeny of Orientia tsutsugamushi: An Analysis Including Two Genomes from Taiwan

Orientia tsutsugamushi is an obligate intracellular bacterium associated with trombiculid mites and is the causative agent of scrub typhus, a life-threatening febrile disease. Strain typing of O. tsutsugamushi is based on its immunodominant surface antigen, 56-kDa type-specific antigen (TSA56). However, TSA56 gene sequence-based phylogenetic analysis is only partially congruent with core genome-based phylogenetic analysis. Thus, this study investigated whether concatenated surface antigen sequences, including surface cell antigen (Sca) proteins, can reflect the genome-scale phylogeny of O. tsutsugamushi. Complete genomes were obtained for two common O. tsutsugamushi strains in Taiwan, TW-1 and TW-22, and the core genome/proteome was identified for 11 O. tsutsugamushi strains. Phylogenetic analysis was performed using maximum likelihood (ML) and neighbor-joining (NJ) methods, and the congruence between trees was assessed using a quartet similarity measure. Phylogenetic analysis based on 691 concatenated core protein sequences produced identical tree topologies with ML and NJ methods. Among TSA56 and core Sca proteins (ScaA, ScaC, ScaD, and ScaE), TSA56 trees were most similar to the core protein tree, and ScaA trees were the least similar. However, concatenated ScaA and TSA56 sequences produced trees that were highly similar to the core protein tree, the NJ tree being more similar. Strain-level characterization of O. tsutsugamushi may be improved by coanalyzing ScaA and TSA56 sequences, which are also important targets for their combined immunogenicity.

Scrub typhus in Northeast India: epidemiology, clinical presentations, and diagnostic approaches

Scrub typhus is one of the most neglected tropical diseases, a leading cause of acute undifferentiated febrile illness in areas of the 'tsutsugamushi triangle', diagnosed frequently in South Asian countries. The bacteria Orientia tsutsugamushi is the causative agent of the disease, which enters the human body through the bite of trombiculid mites (also known as chiggers) of the genus Leptotrombidium deliense. Diagnosis of the disease is challenging, as its early symptoms mimic other febrile illnesses like dengue, influenza and corona viruses. Lack of rapid, reliable and cost-effective diagnostic methods further complicates the identification process. Northeast India, a mountainous region with a predominantly rural tribal population, has witnessed a resurgence of scrub typhus cases in recent years. Various ecological factors, including rodent populations, habitat characteristics and climatic conditions, influence its prevalence. Entomological investigations have confirmed the abundance of vector mites, highlighting the importance of understanding their distribution and the probability of transmission of scrub typhus in the region. Proper diagnosis, awareness campaigns and behavioural interventions are essential for controlling scrub typhus outbreaks and reducing its impact on public health in Northeast India. Further research and community-based studies are necessary to accurately assess the disease burden and implement effective prevention strategies.

Scrub typhus in pregnancy: A report of two cases

Scrub typhus shows a high prevalence in South-East Asia. In pregnant females, it can cause both maternal and fetal adverse outcomes. We report a case series of two women with scrub typhus and their varied outcomes. A 25-year-old primigravida treated for scrub typhus at 23 weeks' gestation presented at 34 weeks with stage three fetal growth restriction (FGR). Caesarean delivery was performed. The neonate had biliary atresia. A 24-year-old primigravida at 31 weeks' gestation was referred from a local hospital due to scrub typhus induced multi-organ dysfunction. She had FGR stage 1 with oligohydramnios. Emergency caesarean delivery was performed in view of acute fetal bradycardia. There is an emerging need for research to reassess what is already known about scrub typhus in pregnancy and to develop techniques for its treatment inorder to achieve a positive maternal and neonatal outcome in these cases.

Acute Pyelonephritis by Scrub Typhus: A Rare Condition

Scrub typhus is prevalent in tropical countries and can have a varied spectrum of presentations from pneumonia, gastroenteritis, lymphadenitis, meningitis, encephalitis, and acute kidney injury to multi-organ dysfunction syndrome. Urinary tract infections like cystitis and pyelonephritis are rarely reported. Here we present an atypical presentation of a 53-year-old female with diabetes mellitus who came to the outpatient department with complaints of high-grade fever, burning micturition, and left flank pain for three days and was initially treated outpatient basis with oral antibiotics. However, her deteriorating condition landed her in an emergency in a state of septic shock. She was initially treated with broad-spectrum conventional antibiotics with other supportive medications. Even after confirmation of the diagnosis of left acute pyelonephritis with septic shock, with appropriate antibiotics, her condition was deteriorating. A sterile urine culture raised suspicion of atypical organisms causing the infection. Proper analysis of her history and readily available investigations of IgM against scrub typhus antigen led to a diagnosis of scrub typhus-related left acute pyelonephritis with septic shock. She was treated adequately with an injection of doxycycline, followed by oral tablets of the same, after which she showed drastic improvement in her symptoms, and then she was discharged. Thus, atypical organisms causing urinary tract infections should be kept always in mind, which can be treated easily and if untreated, can lead to life-threatening consequences.

Clinical and laboratory findings in scrub typhus associated Guillain-Barré syndrome in South Korea

BACKGROUND AND AIMS

Scrub typhus is an endemic disease in the fall season that occurs in a limited number of places known as the Tsutsugamushi Triangle. Peripheral neuropathy is a common complication of scrub typhus. Herein, we encountered several patients with ascending paralysis after scrub typhus infection, who were diagnosed with Guillain-Barré syndrome (GBS). We aimed to investigate the clinical and laboratory characteristics of patients who developed GBS after scrub typhus.

METHODS

Patients were retrospectively recruited from six nationwide tertiary centers in South Korea from January 2017 to December 2021. Patients who had been clinically diagnosed with GBS and confirmed to have scrub typhus via laboratory examination and/or the presence of an eschar before the onset of acute limb paralysis were included. The GBS-associated clinical and electrophysiological characteristics, outcomes, and scrub typhus-associated features were collected.

RESULTS

Of the seven enrolled patients, six were female and one was male. The median time from scrub typhus infection to the onset of limb weakness was 6 (range: 2-14) days. All patients had eschar on their bodies. Four patients (57.1%) were admitted to the intensive care unit and received artificial ventilation for respiratory distress. At 6 months, the median GBS disability score was 2 (range, 1-4) points.

INTERPRETATION

Patients with scrub typhus-associated GBS have a severe clinical presentation and require intensive treatment with additional immunotherapies. Therefore, GBS should be included in the differential diagnosis when peripheral neuropathies develop during scrub typhus treatment. Notably, scrub typhus is associated to GBS.

Case Report: Encephalitis with Initial Manifestation of Orientia Tsutsugamushi Infection Detected by Metagenomic Next-Generation Sequencing

Purpose

Scrub typhus, caused by Orientia tsutsugamushi, is characterized by fever, eschars, lymphadenopathy, and rash. The absence of eschars in some cases makes it difficult to distinguish it from other diseases, complicating the diagnosis process. Atypical Scrub typhus is difficult to diagnose and often leads to delayed treatment. Therefore, early diagnosis and treatment through effective detection methods have high clinical value. Here, a case of scrub typhus with encephalitis symptoms is reported.

Patients and Methods

A 64-year-old man and mNGS testing.

Results

A 64-year-old man developed cough, headache, and fever, dismissing it as a respiratory tract infection. Initial treatment with cephalosporin antibiotics had minimal effect. Admission to the respiratory department showed inflammation in blood tests. Subsequent CT and further treatment provided no improvement. Multidisciplinary discussions and neurology department guidance were conducted to consider the suspected diagnosis of encephalitis in the patient. After improving the mNGS detection, the patient was diagnosed with "Orientia tsutsugamushi encephalitis". After treatment with doxycycline, the patient's symptoms were alleviated. He remained afebrile in follow-up and adhered well to medical advice.

Conclusion

Our case demonstrates that it is difficult to distinguish Orientia tsutsugamushi encephalitis from central nervous system infectious diseases such as meningitis and encephalitis using conventional diagnostic methods, which may affect the treatment plan for the disease. mNGS is a useful and valuable method for early diagnosis of scrub typhus.

Scrub typhus in pregnancy - A threat to maternal and fetal outcome

Background and Objectives

Scrub typhus is an acute febrile illness transmitted by the bite of trombiculid mite in the larval stage. Scrub typhus is rare in pregnancy and there is paucity of data on the clinical outcome of scrub typhus during pregnancy.

Material and Methods

We present five cases of scrub typhus complicating pregnancy who were admitted in the obstetric ward at AIIMS Rishikesh, India during the antenatal period for management.

Results

The first patient presented at term pregnancy in semiconscious state while the rest were preterm between 31 and 34 weeks period of gestation. The age at presentation was 21-31 years. All five had febrile illness of >5 days' duration along with cough. Fever investigations like blood culture, peripheral smear for malarial parasite, dengue serology, widal test, and urine culture were negative. Serology for scrub typhus was positive in all. Once diagnosis was confirmed for scrub typhus, patients were given the drug of choice azithromycin 500 mg twice daily for five days. Scrub typhus complicating pregnancy led to maternal mortality in one patient. It resulted in one preterm delivery, one intrauterine fetal death, and rest three were delivered at term with good perinatal outcome.

Conclusion

Scrub typhus is common in endemic areas like Uttarakhand, India. It has a poor fetal outcome. If diagnosed early and treatment started, maternal and fetal prognosis can be favorable. As large case series are unavailable in literature, it is difficult to predict the course of disease which at times may be fulminant.

Molecular detection of Orientia tsutsugamushi in ectoparasites & their small mammal hosts captured from scrub typhus endemic areas in Madurai district, India

BACKGROUND OBJECTIVES

Scrub typhus, caused by Orientia tsutsugamushi present in small mammals harbouring the ectoparasites. A study was undertaken to detect the pathogen present in small mammals and its ectoparasites in the scrub typhus-reported areas.

METHODS

The small mammals (rodents/shrews) and its ectoparasites were screened for O. tsutsugamushi using nested PCR amplification of the groEL gene. Small mammals were collected by trapping and screened for ectoparasites (mites, ticks and fleas) by combing method.

RESULTS

All the chigger mites collected were tested negative for O. tsutsugamushi . Interestingly, adult non-trombiculid mites ( Oribatida sp., Dermanyssus gallinae ), fleas ( Xenopsylla astia, X. cheopis, Ctenophalides felis and Ctenophalides sp.) and ticks ( Rhipicephalus sanguineus , R. haemaphysaloides ) screened were found to be positive for O. tsutsugamushi , which the authors believe is the first report on these species globally. Bandicota bengalensis with O. tsutsugamushi infection is reported for the first time in India. The O. tsutsugamushi groEL sequences from the positive samples were similar to the reference strains, Karp and Ikeda and phylogenetically clustered in clade IV with less evolutionary divergence. The blood samples of Rattus rattus , Suncus murinus and B. bengalensis collected from this area were tested positive for O. tsutsugamushi ; interestingly, the sequence similarity was much pronounced with their ectoparasites indicating the transmission of the pathogen to host or vice versa .

INTERPRETATION CONCLUSIONS

The outcome of the present investigations widened our scope on the pathogens present in ectoparasites and rodents/shrews from this area. This will help to formulate the required vector control methods to combat zoonotic diseases.

CagA-positive Helicobacter pylori may promote and aggravate scrub typhus

Helicobacter pylori (H. pylori) infection may alter the host's resistance to tsutsugamushi disease pathogens through the Th1 immune response, leading to potential synergistic pathogenic effects. A total of 117 scrub typhus cases at Beihai People's Hospital and affiliated hospitals of Youjiang University for Nationalities and Medical Sciences were studied from January to December 2022, alongside 130 healthy individuals forming the control group. All participants underwent serum H. pylori antibody testing. The prevalence of H. pylori infection was significantly higher among scrub typhus patients (89.7%) compared to healthy individuals (54.6%) (p < 0.05). Moreover, type I H. pylori infection was notably more prevalent in scrub typhus cases (67.5%) compared to healthy individuals (30%) (p < 0.05). Multifactorial analysis demonstrated type I H. pylori infection as an independent risk factor for scrub typhus (adjusted odds ratio: 2.407, 95% confidence interval: 1.249-4.64, p = 0.009). Among scrub typhus patients with multiple organ damage, the prevalence of type I H. pylori infection was significantly higher (50.6%) than type II H. pylori infection (15.4%) (χ2 = 4.735, p = 0.030). These results highlight a higher incidence of H. pylori infection in scrub typhus patients compared to the healthy population. Additionally, type I H. pylori strain emerged as an independent risk factor for scrub typhus development. Moreover, individuals infected with type I H. pylori are more susceptible to multiple organ damage. These findings suggest a potential role of H. pylori carrying the CagA gene in promoting and exacerbating scrub typhus.

Case report of scrub typhus with bilateral acute sensorineural hearing loss and cerebral salt-wasting disease

Scrub typhus is a re-emerging and endemic disease in the Asia Pacific region caused by Orientia tsutsugamushi. We present a 65-year-old male from Sri Lanka who presented with fever, bilateral acute sensorineural hearing loss, and confusion. On examination, he was dehydrated. Significant orthostatic hypotension and an eschar were noted. Investigations revealed hyponatraemia with elevated urine sodium, reduced serum osmolality, and normal urine osmolality suggestive of cerebral salt wasting. After initial hydration with 0.9% NaCl, hyponatraemia was corrected with 3% NaCl. Oral doxycycline was prescribed, and he showed dramatic clinical improvement. A diagnosis of typhus must be considered in a patient presenting with a febrile illness and acute hearing loss. Cerebral salt-wasting disease should be considered in a patient with typhus who develops hyponatraemia with dehydration. Furthermore, acute sensorineural hearing loss in both ears is an important manifestation of the disease.

Hepatopathy in Scrub Typhus: Clinical Presentation, Association With Morbidity and Impact on Outcome

INTRODUCTION

Acute liver injury accompanies tropical fevers like scrub typhus. This study was undertaken to evaluate liver injury in scrub typhus and its association with the disease severity.

METHODS

This was a single-centre prospective, observational study on in-patients of scrub typhus from north India. All patients were categorized on basis of elevation of transaminases as having normal or abnormal liver function. Those with hepatopathy were sub-categorized as having mild, moderate, severe or very severe liver injury.

RESULTS

Liver dysfunction was present in 76/109 of the patients and was significantly associated with eschar, clinically discernible hepatomegaly and splenomegaly. Shock, renal and respiratory insufficiency, need for intensive care and oxygen supplementation were also significantly associated with hepatopathy. Duration of hospitalization and mortality were comparable in patients with/without liver injury; however delayed defervescence (6.2+3.8 vs. 4.5+2.5 days; p=0.025) was observed with hepatopathy. Icterus (p=0.001), hepatomegaly (p=0.015), thrombocytopenia (p<0.001) and raised erythrocyte sedimentation rate (ESR) (p=0.003) were significantly observed with increasing grade of liver injury.  Conclusion: Liver dysfunction and its increased severity in scrub typhus did not translate into increased morbidity and/or poor outcomes.