Sensorineural hearing loss as an atypical presentation of typhoid fever: A case report

Typhoid fever, also known as enteric fever, is a multisystemic infection primarily caused by Salmonella enterica serotype Typhi, and less commonly by Salmonella enterica serotypes Paratyphi A, B, and C. The classic presentation includes fever, malaise, diffuse abdominal pain, and constipation. If left untreated, typhoid fever can progress to delirium, obtundation, intestinal haemorrhage, bowel perforation, and death within a month of onset. However, the clinical course can deviate from the classic stepladder fever pattern, which now occurs in as few as 12% of cases.1 In this report, we describe an atypical presentation as sensorineural hearing loss in an otherwise healthy young male.

Clinical and antimicrobial susceptibility profile of typhoid fever in children in the era of antibiotic resistance

Enteric fever remains a significant public health problem in low- and middle-income countries with further challenges from emerging antimicrobial resistance. Our prospective study evaluated the current clinical and antimicrobial susceptibility profile of enteric fever in 88 children and compared it to previously established literature. Enteric fever usually presents with nonspecific signs and symptoms, with predominant respiratory complaints. A paradigm shift in the antimicrobial sensitivity pattern has been noted, with increasing resistance for first-line antibiotics and older antibiotics such as ampicillin, cotrimoxazole, and chloramphenicol showing good sensitivity. Thus, the introduction of the latter merits consideration.

Practical approach to a patient with fever who travelled to the tropics

By 2030, an estimated 2 billion international tourist trips are expected annually worldwide, with citizens of Poland as important contributors. Illness rates among returnees from developing regions range between 43% and 79%. Properly diagnosing fever in these travelers is vital due to potentially serious implications. After visiting tropical and subtropical zones, the main health complaints are diarrhea, fever, and skin lesions. A reliable diagnosis begins with taking a comprehensive travel history and identifying potential risks. In travelers returning from sub‑Saharan Africa, malaria caused by Plasmodium falciparum is the main cause of fever, affecting 50 in every 1000 cases. Among returnees from Southeast Asia, dengue is dominant, occurring in 50-60 per 1000 cases, and its prevalence rises significantly nowadays. Other significant diseases include chikungunya, Zika, typhoid fever, amebic liver abscess, and occasionally viral hemorrhagic fevers. SARS‑CoV‑2 and influenza viruses are crucial pathogens as well. An in‑depth assessment of the travel history, combined with knowledge on tropical diseases, are key to the diagnostic process, and algorithms may be helpful in selecting appropriate tests and treatment methods.

Case Report: A Case of Complicated Typhoid Fever with Rhabdomyolysis and Hemophagocytic Lymphohistiocytosis

Typhoid fever can have diverse extra-intestinal complications including encephalitis, Guillain-Barré syndrome, endocarditis, myocarditis, osteomyelitis, renal abscess, and splenic abscesses. Secondary hemophagocytic lymphohistiocytosis with rhabdomyolysis is a rare complication of typhoid fever. Here, we present the case of an adolescent with typhoid fever complicated by rhabdomyolysis and hemophagocytic lymphohistiocytosis.

Large outbreak of typhoid fever on a river cruise ship used as accommodation for asylum seekers, the Netherlands, 2022

On 6 April 2022, the Public Health Service of Kennemerland, the Netherlands, was notified about an outbreak of fever and abdominal complaints on a retired river cruise ship, used as shelter for asylum seekers. The diagnosis typhoid fever was confirmed on 7 April. An extensive outbreak investigation was performed. Within 47 days, 72 typhoid fever cases were identified among asylum seekers (n = 52) and staff (n = 20), of which 25 were hospitalised. All recovered after treatment. Consumption of food and tap water on the ship was associated with developing typhoid fever. The freshwater and wastewater tanks shared a common wall with severe corrosion and perforations, enabling wastewater to leak into the freshwater tank at high filling levels. Salmonella Typhi was cultured from the wastewater tank, matching the patient isolates. In the freshwater tank, Salmonella species DNA was detected by PCR, suggesting the presence of the bacterium and supporting the conclusion of contaminated freshwater as the probable source of the outbreak. Outbreaks of uncommon infections may occur if persons from endemic countries are accommodated in crowded conditions. Especially when accommodating migrants on ships, strict supervision on water quality and technical installations are indispensable to guarantee the health and safety of the residents.

Typhoid Fever Presenting with Ileal Perforation and Gastric Perforation

Typhoid fever is caused by Salmonella typhi and Salmonella paratyphi. It is a disease of developing countries and is seen among people of low socio-economic status. Patients can develop complications like typhoid intestinal perforation which is associated with higher mortality. A 15-year-old female presented to the emergency pediatric unit with fever, abdominal pain and abdominal distension. She was septic, in respiratory distress, and had marked generalized abdominal tenderness with guarding. An assessment of generalized peritonitis secondary to typhoid intestinal perforation was made. She had exploratory laparotomy with intra-operative findings of ileal perforation and gastric perforation. She had repair of the intestinal and gastric perforations. Our patient presented late with concurrent use of NSAIDs and overwhelming sepsis which likely contributed to the gastric perforation as this is not a usual finding in patients with typhoid intestinal perforation. Gastric perforation is an unusual finding in patients with typhoid intestinal perforation. Typhoid fever and its complications can be easily prevented by the provision of safe water, proper facilities for sanitation, and practicing good hygiene.

Typhoid spondylodiscitis of the cervical spine

Spinal infection comprises pyogenic and non-pyogenic spondylodiscitis. This condition may manifest with non-specific clinical symptoms, elevated infective parameters and imaging findings that are difficult to distinguish. The cornerstone of a definitive diagnosis and subsequent successful treatment lies in tissue analysis through culture and histopathological studies. In this context, we present a case of Salmonella pyogenic spondylodiscitis affecting the C5/C6 vertebrae, complicated by Salmonella bacteraemia and characterised by mechanical neck pain that curtails daily activities and overall functioning, although without neurological deficits. The uniqueness of this case stems from its occurrence in an immunocompetent individual from a non-endemic area, with no identifiable sources of Salmonella infection or preceding gastrointestinal symptoms.

Typhoid fever

Typhoid fever is an invasive bacterial disease associated with bloodstream infection that causes a high burden of disease in Africa and Asia. Typhoid primarily affects individuals ranging from infants through to young adults. The causative organism, Salmonella enterica subsp. enterica serovar Typhi is transmitted via the faecal-oral route, crossing the intestinal epithelium and disseminating to systemic and intracellular sites, causing an undifferentiated febrile illness. Blood culture remains the practical reference standard for diagnosis of typhoid fever, where culture testing is available, but novel diagnostic modalities are an important priority under investigation. Since 2017, remarkable progress has been made in defining the global burden of both typhoid fever and antimicrobial resistance; in understanding disease pathogenesis and immunological protection through the use of controlled human infection; and in advancing effective vaccination programmes through strategic multipartner collaboration and targeted clinical trials in multiple high-incidence priority settings. This Primer thus offers a timely update of progress and perspective on future priorities for the global scientific community.

Case Report: An Imported Case of Typhoid Fever Combined with Rhabdomyolysis and Multiple Organ Lesions in China

Here, we report a case of blood culture-confirmed typhoid fever, rhabdomyolysis, and multiple organ damage that arrived in our country from overseas. A 23-year-old male patient presented at our hospital with fever and muscle pain; the condition progressed rapidly. Six days after the onset of symptoms, the patient developed rhabdomyolysis and liver/kidney damage; levels of creatine kinase (CK; maximum peak: 729,869 U/L) and myoglobin (> 3,000 ng/mL) were extremely high, although the extent of renal damage was relatively mild. Blood culture showed Salmonella typhi. The patient received a combination of meropenem and levofloxacin anti-infective therapy, as well as fluid and nutritional metabolic support. He gradually recovered and was discharged after two negative blood cultures. This case highlights the fact that typhoid-induced rhabdomyolysis is a serious, life-threatening disease and that the levels of CK and myoglobin are useful indicators for evaluating typhoid-induced rhabdomyolysis. Clinicians should remain vigilant regarding travel-related illnesses associated with enteric fever.

Novel Heptaplex PCR-Based Diagnostics for Enteric Fever Caused by Typhoidal Salmonella Serovars and Its Applicability in Clinical Blood Culture

Enteric fever is caused by typhoidal Salmonella serovars (Typhi, Paratyphi A, Paratyphi B, and Paratyphi C). Owing to the importance of Salmonella serovars in clinics and public hygiene, reliable diagnostics for typhoidal serovars are crucial. This study aimed to develop a novel diagnostic tool for typhoidal Salmonella serovars and evaluate the use of human blood for clinically diagnosing enteric fever. Five genes were selected to produce specific PCR results against typhoidal Salmonella serovars based on the genes of Salmonella Typhi. Heptaplex PCR, including genetic markers of generic Salmonella, Salmonella enterica subsp. enterica, and typhoidal Salmonella serovars, was developed. Typhoidal Salmonella heptaplex PCR using genomic DNAs from 200 Salmonella strains (112 serovars) provided specifically amplified PCR products for each typhoidal Salmonella serovar. These results suggest that heptaplex PCR can sufficiently discriminate between typhoidal and nontyphoidal Salmonella serovars. Heptaplex PCR was applied to Salmonella-spiked blood cultures directly and provided diagnostic results after 12- or 13.5-h blood culture. Additionally, it demonstrated diagnostic performance with colonies recovered from a 6-h blood culture. This study provides a reliable DNA-based tool for diagnosing typhoidal Salmonella serovars that may be useful in clinical microbiology and epidemiology.

Utilization Of The Complete Blood Count In Diagnosing Endemic Diseases In Pakistan

Numerous infectious diseases, including enteric fever, malaria, dengue fever, and, most recently, coronavirus disease-2019, are prevalent in Pakistan. All these diseases have overlapping clinical symptoms and can present a diagnostic challenge for the general practitioner. Since definitive testing for these disorders is time-consuming and expensive, basic clinical testing, such as a complete blood count, should be utilised to supplement clinical diagnosis, when possible. The current narrative review was planned to present specific alterations in haematological parameters for each of these disorders. The review was intended as a guide for practising physicians in their decision-making.

Case of Carbapenem-Resistant Salmonella Typhi Infection, Pakistan, 2022

Salmonella Typhi infection in a patient in Pakistan initially responded to standard treatment but failed to respond to subsequent treatment. The first strain was susceptible to carbapenems and azithromycin; subsequent strains harbored the NDM-5 gene. Treatment with a combination of intravenous meropenem and colistin was successful. Carbapenem-resistant Salmonella Typhi emergence will hinder treatment.

Typhoid fever due to laboratory-acquired Salmonella Typhi, confirmed by core genome multi-locus sequence typing

We present a case of laboratory-acquired Salmonella Typhi, resulting in hospitalization of a technician. Blood and stool cultures revealed a S. Typhi strain, identical to the strain with which the employee had recently worked, confirmed using core-genome multilocus sequence typing. The incident occurred despite working in a biosafety cabinet.

Variations of blood viscosity in acute typhoid fever: A cross-sectional study

Typhoid fever (TF) is a systemic infection caused by Salmonella Typhi (Salmonella Enterica) transmitted through contaminated water, food, or contact with infected individuals. In various infectious diseases, blood viscosity (BV) is affected by changes in hemoglobin concentrations and acute phase reactants. Inflammatory responses can lead to elevated plasma protein levels and further affect BV. This study aimed to investigate BV changes in patients with acute TF. A cross-sectional study was performed involving 55 patients with acute TF compared to 38 healthy controls. BV and inflammatory parameters were measured in both groups. TF patients showed reduced blood cells compared to healthy controls (p=0.001). Additionally, plasma total protein (TP) levels significantly increased to 10.79±1.05 g/L in TF patients compared to 7.035±1.44 g/L in healthy controls (p=0.03). Hematocrit (HCT) levels were 11.67±2.89% in TF patients and 12.84±2.02% in healthy controls (p=0.07), suggesting a trend towards increased BV in TF patients. Elevated BV is involved in the pathogenesis of different inflammatory and infectious diseases. The increased BV in TF patients may raise the risk of complications. Therefore, monitoring BV might be a crucial tool in TF patients, mainly in the high-risk group, for early detection of cardiovascular complications.

Surface plasmon resonance-based oligonucleotide biosensor for Salmonella Typhi detection

Due to high mortality rates, typhoid fever still is one of the major health problems in the world, particularly in developing countries. The lack of highly specific and sensitive diagnostic tests and the great resemblance of typhoid fever symptoms to other diseases made the false-negative diagnosis a major challenge in typhoid fever management. Hence, we decided to design a Surface Plasmon Resonance (SPR) based biosensor for specific detection of Salmonella typhi through DNA hybridization. The results showed that the 10 nM of the synthetic target sequence, as well as 1 nM of PCR product, were the lowest feasible detected concentrations by the designed biosensor. This genosensor was also found to significantly distinguish the complementary sequence with the accuracy of one base mismatch sequence. The surface of the chip can be regenerated with NaOH solution and used for consecutive diagnosis. Therefore, the function of the designed biosensor indicates its high potential for Salmonella typhi detection practice.

Role of TaqMan array card in determining causative organisms of acute febrile illness in hospitalized patients

BACKGROUND

Acute febrile illness (AFI) is a prevalent disease in developing countries that is difficult to diagnose due to the diversity of infectious organisms and the poor quality of clinical diagnosis. TaqMan array card (TAC) can detect up to 35 AFI-associated organisms in 1.5 h, addressing diagnostic demands. In this study, we aimed to evaluate the role of TAC in determining the causative organisms in hospitalized AFI patients.

METHODS

The study had a cross-sectional design and enrolled 120 admitted patients with persistent fever for three or more days from the medicine ward of Chittagong Medical College Hospital (CMCH) and Bangladesh Institute of Tropical and Infectious Diseases Hospital (BITID). Blood samples were collected and then subjected to automated BacT/Alert blood culture, microbial culture, TAC assay, and typhoid/paratyphoid test.

RESULTS

The total number of study participants was 120, among them 48 (40%) samples showed a positive result in TAC card, 29 (24.16%) were TP positive and nine (7.51%) were culture positive. The number of organisms detected by the TAC card was 13 bacteria, three viruses, one protozoan, and one fungus. The sensitivity and specificity of the TAC assay for different bacterial pathogen compared to blood culture was 44.44%, and 90.99%, respectively. In contrast, the TP test had a sensitivity and specificity of 100% and 80%, respectively, compared to the blood culture test.

CONCLUSION

TAC can be a handful tool for detecting multiple organisms in AFI with high specificity which can facilitate early diagnosis of different pathogens contributing to AFI.

Bifunctionalized nanobioprobe based rapid color-shift assay for typhoid targeting Vi capsular polysaccharide

Typhoid fever is an acute illness caused by Salmonella Typhi and the current diagnostic gap leads to inaccurate, over-diagnosis of typhoid leading to excessive use of antibiotics. Herein, to address the challenges we describe a new rapid color-shift assay based on a novel bifunctional nanobioprobe (Vi-AgNP probe) that is functionalized with specific biomarker Vi polysaccharide and also has the co-presence of Ag as urease inhibitor. The immunoreactions between the Vi with specific antibodies (Abs) present in typhoid patient sample forms a shielding barrier over Vi-AgNP probe rendering the urease to be active, generating colored output. Vi polysaccharide coating on the AgNP was visualized using HRTEM. TEM was performed to get insight into shielding barrier formation by the Abs. MST (microscale thermophoresis) data showed less binding Kd of 7.43 μM in presence of Abs whereas probe with urease showed efficient binding with Kd 437 nM. The assay was validated using 53 human sera samples and proven effective with 100% sensitivity. The assay showed relative standard deviation (RSD) of 4.3% estimated using rabbit anti-Vi Abs. The entire procedure could be completed within 15 min. Unlike lateral flow based assays, our assay does not require multiple combination of Abs for detection. The assay format was also found compatible in paper strip test that provides promising opportunities to develop low-cost on-spot assay for clinical diagnostics.

[Biliary peritonitis: diagnostic and therapeutic aspects]

AIMS

The aim was to describe the diagnostic and therapeutic aspects of biliary peritonitis.

PATIENTS AND METHODS

This was a descriptive cross-sectional study with retrospective collection over a period of 10 years including patients operated on for biliary peritonitis.

RESULTS

We collected 10 cases of biliary peritonitis with an average age of 38 years with a sex ratio of 2.3. Two patients presented with an abdominal contusion following a road traffic accident. Maximum abdominal pain in the right hypochondrium was present in three patients, signs of peritoneal irritation in all patients, positive Widal and Felix serodiagnosis in eight patients. At midline laparotomy, the gallbladder was perforated in three patients, gangrenous in five, phlegmonous in one, sclero-atrophic in one. Cholecystectomy was performed in all patients. Biliary peritonitis was of traumatic origin in two patients, and typhoid in eight. Postoperatively, there were four cases of sepsis and three cases of parietal suppuration. Three patients died.

CONCLUSION

Biliary peritonitis discovered during laparotomies for peritonitis, was secondary to typhoid cholecystitis, and had a high morbidity and mortality.

Acute febrile illness among outpatients seeking health care in Bangladeshi hospitals prior to the COVID-19 pandemic

Understanding the distribution of pathogens causing acute febrile illness (AFI) is important for clinical management of patients in resource-poor settings. We evaluated the proportion of AFI caused by specific pathogens among outpatients in Bangladesh. During May 2019-March 2020, physicians screened patients aged ≥2 years in outpatient departments of four tertiary level public hospitals. We randomly enrolled patients having measured fever (≥100.4°F) during assessment with onset within the past 14 days. Blood and urine samples were tested at icddr,b through rapid diagnostic tests, bacterial culture, and polymerase chain reaction (PCR). Acute and convalescent samples were sent to the Centers for Disease Control and Prevention (USA) for Rickettsia and Orientia (R/O) and Leptospira tests. Among 690 patients, 69 (10%) had enteric fever (Salmonella enterica serotype Typhi orSalmonella enterica serotype Paratyphi), 51 (7.4%) Escherichia coli, and 28 (4.1%) dengue detected. Of the 441 patients tested for R/O, 39 (8.8%) had rickettsioses. We found 7 (2%) Leptospira cases among the 403 AFI patients tested. Nine patients (1%) were hospitalized, and none died. The highest proportion of enteric fever (15%, 36/231) and rickettsioses (14%, 25/182) was in Rajshahi. Dhaka had the most dengue cases (68%, 19/28). R/O affected older children and young adults (IQR 8–23 years) and was detected more frequently in the 21–25 years age-group (17%, 12/70). R/O was more likely to be found in patients in Rajshahi region than in Sylhet (aOR 2.49, 95% CI 0.85–7.32) between July and December (aOR 2.01, 1.01–5.23), and who had a history of recent animal entry inside their house than not (aOR 2.0, 0.93–4.3). Gram-negative Enterobacteriaceae were the most common bacterial infections, and dengue was the most common viral infection among AFI patients in Bangladeshi hospitals, though there was geographic variability. These results can help guide empiric outpatient AFI management.

Estimating typhoid incidence from community-based serosurveys: a multicohort study

BACKGROUND

The incidence of enteric fever, an invasive bacterial infection caused by typhoidal Salmonellae (Salmonella enterica serovars Typhi and Paratyphi), is largely unknown in regions without blood culture surveillance. The aim of this study was to evaluate whether new diagnostic serological markers for typhoidal Salmonella can reliably estimate population-level incidence.

METHODS

We collected longitudinal blood samples from patients with blood culture-confirmed enteric fever enrolled from surveillance studies in Bangladesh, Nepal, Pakistan, and Ghana between 2016 and 2021 and conducted cross-sectional serosurveys in the catchment areas of each surveillance site. We used ELISAs to measure quantitative IgA and IgG antibody responses to hemolysin E and S Typhi lipopolysaccharide. We used Bayesian hierarchical models to fit two-phase power-function decay models to the longitudinal antibody responses among enteric fever cases and used the joint distributions of the peak antibody titres and decay rate to estimate population-level incidence rates from cross-sectional serosurveys.

FINDINGS

The longitudinal antibody kinetics for all antigen-isotypes were similar across countries and did not vary by clinical severity. The seroincidence of typhoidal Salmonella infection among children younger than 5 years ranged between 58·5 per 100 person-years (95% CI 42·1-81·4) in Dhaka, Bangladesh, to 6·6 per 100 person-years (4·3-9·9) in Kavrepalanchok, Nepal, and followed the same rank order as clinical incidence estimates.

INTERPRETATION

The approach described here has the potential to expand the geographical scope of typhoidal Salmonella surveillance and generate incidence estimates that are comparable across geographical regions and time.

FUNDING

Bill & Melinda Gates Foundation.

TRANSLATIONS

For the Nepali, Bengali and Urdu translations of the abstract see Supplementary Materials section.

Clinical manifestations and microbiological features between indigenous and imported enteric fever in Taiwan, 2010-2020

Previous studies had showed that indigenous clones of Salmonella Typhi and S. Paratyphi were originally imported from other countries in Taiwan. We presented the clinical manifestations and laboratory findings of indigenous and imported enteric fever cases in Taiwan in the current decade. We retrospectively reviewed typhoid and paratyphoid fever cases in two medical centers of Chang Gung Memorial Hospitals in 2010-2020. A total of 37 enteric fever cases including 24 typhoid fever and 13 paratyphoid fever were recorded. There were 20 indigenous cases, 16 imported cases, and one indetermined case. Splenomegaly and hepatitis were more frequent in typhoid fever than in paratyphoid fever (P < 0.05). Imported cases had more ciprofloxacin non-susceptibility rate (8/16, 50.0%) than indigenous cases (2/20, 10%). Indigenous ciprofloxacin non-susceptible S. Typhi isolates were found in 2018. One indigenous S. Paratyphi B isolate was multi-drug resistant (MDR) to chloramphenicol, ampicillin, and trimethoprim/sulfamethoxazole.

A clinical audit to evaluate antibiotic prescribing practice in pediatric patients admitted for enteric fever. Rationalizing antibiotic stewardship program

To evaluate the antibiotic prescribing practice in pediatric patients for enteric fever, and to assess the need of developing and implementing the Antibiotic Stewardship Program (ASP) for the hospital. A prospective audit was completed in the pediatric ward of tertiary care hospital of Lahore for one year. Blood culture reports were collected from microbiology departed and clinical data were assessed regarding the choice of antibiotics, frequency, dosage and clinical outcome. All the statistics were analyzed using SPSS software and compared with the guidelines. Out of 157 cases hospitalized with suspicion of enteric fever, 137 cultures were positive for salmonella. Monotherapy of ceftriaxone (70%) was prescribed mostly as empirical therapy. About 20% of patients received a combination of antibiotics empirically. Susceptibility reports showed only 7 cases were of non-resistant typhoid, 15 multi-drug resistant and 115 extensively drug-resistant. Nearly 46% of patients were discharged earlier whose empirical therapy was changed either before or promptly after susceptibility reporting. Commonly used definitive antibiotics (32%) were a combination of azithromycin and meropenem. Inappropriate use of antibiotics was noted frequently as compared to the guidelines. However, recommendations themselves need to be reviewed as antibiotic resistance patterns are changing drastically.

Detection of Salmonella Typhi in Bile by Quantitative Real-Time PCR

In countries where the incidence of typhoid fever is high, fecal material from short-term carriers of Salmonella Typhi contaminates inadequately treated water supplies. As treated water supplies and improved sanitation become available, chronic (mainly gallbladder) carriers of S. Typhi become important. The objective of this study was to develop a method for detection of S. Typhi in bile by quantitative real-time PCR (qPCR) in patients undergoing cholecystectomy. We evaluated sensitivity and specificity of probesets that target oriC, viaB, fliC-d, STY0201, and stoD. We optimized DNA extraction from bile and compared the sensitivity of culture and our qPCR method to detect S. Typhi in bile samples containing various cephalosporins. With the use of an optimized DNA extraction technique, our limit of detection of S. Typhi in spiked human bile samples was 7.4 × 102 CFU/mL. We observed that S. Typhi could be detected by qPCR in samples containing cefazolin, cefotaxime, or ceftriaxone whereas culture could only detect Typhi in samples containing cefazolin but not cefotaxime or ceftriaxone. Our qPCR detection method for S. Typhi in bile should be preferred in areas where antibiotic usage is common. IMPORTANCE New Salmonella Typhi conjugate vaccines have been deployed, which will potentially lead to a fall in incidence rates of typhoid fever in endemic areas. Identification of chronic carriers of S. Typhi will be important as these individuals can be a potential source of transmission to susceptible persons. To address this public health concern, we have developed a novel method to detect S. Typhi in bile using real-time PCR. Our method can be used to identify carriers of S. Typhi among patients undergoing cholecystectomy (gallbladder removal surgery). The sensitivity of our molecular-based assay was superior to culture when performed in the presence of antibiotics commonly used during surgery. Our methodology will complement efforts to eliminate typhoid disease.

Fever in the Returning Traveler

BACKGROUND

It is predicted that approximately two billion tourist trips to foreign countries will be taken worldwide each year by 2030. Germany has long been among the most active countries in tourism. The frequency of illness among persons returning from developing and newly industrialized countries is 43-79%. The appropriate diagnosis of fever in returning travelers is a clinically important matter, as it can be a sign of a life-threatening illness.

METHODS

This review is based on publications (2001-2022) retrieved by a selective search in PubMed for studies on the epidemiology, diagnosis, and treatment of febrile illnesses in returning travelers, or on specific tropical diseases.

RESULTS

Diarrhea, fever, and skin changes are the most common manifestations of disease after travel to tropical and sub - tropical areas. The diagnostic evaluation should be performed in a series of steps, beginning with a precise travel history and the identification of specific risk factors. Among travelers returning from sub-Saharan Africa, Plasmodium falciparum malaria is the most common cause of fever on presentation to centers for infectious diseases and tropical medicine, affecting approximately 50 per 1000 travelers. Among persons returning from travel to Southeast Asia, dengue fever is the most common infectious disease, affecting 50-160 per 1000 travelers. Further potentially dangerous diseases include chikungunya and zika fever, typhoid and paratyphoid fever, amoebic liver abscess, visceral leishmaniasis (kala-azar), leptospirosis, and, very rarely, imported cases of viral hemorrhagic fever. COVID-19 and influenza are important differential diagnoses.

CONCLUSION

The differential diagnosis can be narrowed by thorough history-taking with particular attention to the patient's travel route, combined with a good knowledge of the geographic spread and incubation times of the main tropical diseases. Algorithms help clinicians to focus the diagnostic work-up and select the appropriate further laboratory tests and diagnostic procedures.

From Gut to Heart: Extensively Drug-resistant <em>Salmonella</em> <em>typhi</em> with Multi System Involvement

Extensively drug-resistant (XDR) salmonella typhi is a gram-negative bacillus, transmitted by feco-oral route. Its systemic manifestations are protean. Untreated enteric fever carries high morbidity and mortality. Life-threatening complications are mainly extra-intestinal, and include involvement of central nervous system, lungs, liver, and genitourinary system. We report a case of a young girl presenting to a hospital in Karachi with a 1-week history of fever, rigors, abdominal pain, watery diarrhea, nausea, and anorexia. She developed toxic myocarditis, pulmonary edema, septic shock, and coagulopathy. Multi-drug-resistant (MDR) salmonella typhi was isolated from blood cultures. Her symptoms resolved after intravenous antibiotics and she completely recovered. Key Words: Myocarditis, Salmonella typhi, Coagulopathy.

Coinfection of enteric fever and hepatitis A

Poor sanitation and contaminated food and water are major risk factors for several infectious diseases like enteric fever and hepatitis A, but their coinfection is uncommon. Although the liver is frequently affected in typhoid fever, substantial hepatic dysfunction in an appropriately treated patient is uncommon. Our patient had high-grade fever with mild transaminitis and blood culture that grew Salmonella typhi Despite being treated with culture-sensitive antibiotic at adequate dosage, he developed jaundice and had worsening transaminitis (>1000 IU/L) which was suggestive of hepatotropic virus infection. Hepatitis A IgM was positive. He was treated appropriately with which clinical and laboratory parameters resolved.

Typhoid appendicitis and 'the man from Istanbul'

We describe typhoid appendicitis in a 19-year-old girl. The appendix showed aggregates of macrophages in the mucosa and in the wall. Blood culture yielded Salmonella enterica serovar Typhi. The presence of macrophages in an appendicectomy specimen should prompt the pathologist to consider the possibility of typhoid fever, even in the absence of supporting microbiological investigations.

Early and Rapid Detection of Typhoid Fever by Nested PCR in Blood

Typhoid fever caused by Salmonella typhi is one of the major health problems in developing countries including Bangladesh. Still now blood culture is gold standard method for diagnosing typhoid fever, but this method is laborious, requires several days and detection rate is low. Failure of early laboratory diagnosis often leads to increased morbidity and mortality. This study was intended to apply a nested PCR in blood for early diagnosis of typhoid fever. In this cross sectional study blood samples were collected from 200 suspected typhoid fever patients attending Mymensingh Medical College Hospital, Bangladesh. Nested Polymerase Chain Reaction (n PCR) of flagellin gene was done in all the blood samples. At the same time all blood samples were subjected to culture by lytic centrifugation method. Culture positive isolates were identified as S. typhi by biochemical tests. Among the 200 blood samples, 57 (28.5%) were positive for S. typhi on nested PCR where as blood culture was positive for S. typhi in 16 (8%) samples. Among the 57 PCR positive samples, only 15 (26.3%) samples were culture positive for S. typhi and rest 42 (73.7%) were culture negative. So, in culture negative cases PCR can be used as a rapid diagnostic test for diagnosing typhoid fever. Considering time requirement, PCR takes one day, whereas blood culture takes 3 or more days to confirm diagnosis.

The molecular basis of extensively drug-resistant Salmonella Typhi isolates from pediatric septicemia patients

Sepsis is a syndromic response to infections and is becoming an emerging threat to the public health sector, particularly in developing countries. Salmonella Typhi (S. Typhi), the cause of typhoid fever, is one primary cause of pediatric sepsis in typhoid endemic areas. Extensively drug-resistant (XDR) S. Typhi is more common among pediatric patients, which is responsible for over 90% of the reported XDR typhoid cases, but the majority of antibiotic resistance studies available have been carried out using S. Typhi isolates from adult patients. Here, we characterized antibiotic-resistance profiles of XDR S. Typhi isolates from a medium size cohort of pediatric typhoid patients (n = 45, 68.89% male and 31.11% female) and determined antibiotic-resistance-related gene signatures associated with common treatment options to typhoid fever patients of 18 XDR S. Typhi representing all 45 isolates. Their ages were 1–13 years old: toddlers aging 1–2 years old (n = 9, 20%), pre-schoolers aging 3–5 years old (n = 17, 37.78%), school-age children aging 6–12 years old (n = 17, 37.78%), and adolescents aging 13–18 years old (n = 2, 4.44%). Through analyzing bla_TEM1, dhfR7, sul1, and catA1genes for multidrug-resistance, qnrS, gyrA, gyrB, parC, and parE for fluoroquinolone-resistance, bla_CTX-M-15 for XDR, and macAB and acrAB efflux pump system-associated genes, we showed the phenotype of the XDR S. Typhi isolates matches with their genotypes featured by the acquisitions of the genes bla_TEM1, dhfR7, sul1, catA1, qnrS, and bla_CTX-M-15 and a point mutation on gyrA. This study informs the molecular basis of antibiotic-resistance among recent S. Typhi isolates from pediatric septicemia patients, therefore providing insights into the development of molecular detection methods and treatment strategies for XDR S. Typhi.

Parsonage-Turner Syndrome Following Typhoid Vaccination

Parsonage-Turner syndrome is a rare neurological disease of varying etiology characterized by severe shoulder pain, muscle weakness, and atrophy. Mechanisms are unclear, but are thought to be genetic and immune-mediated reactions. Rarely, Parsonage-Turner syndrome occurs as a side effect of vaccination. A 20-year-old male who worked as a soldier visited the military hospital because of shoulder pain after vaccination against typhoid and was diagnosed with Parsonage-Turner syndrome based on electromyography and joint magnetic resonance imaging. Pain was controlled with a nerve block. Intravenous immunoglobulin was administered for improvement of neurologic symptoms. This case suggests that Parsonage-Turner syndrome should be considered as a side effect of vaccination. To the best of our knowledge, this is the first report of Parsonage-Turner syndrome following vaccination in Korea.

Diagnostic Value of Clinical Profile and Proposed a Clinical Diagnostic Criterion of Enteric Fever

Enteric fever is a common bacterial infection in the tropics and endemic to Bangladesh. The volatile manifestations of enteric fever construct this disease a true diagnostic confrontation. There are limited current objective data on the value of individual clinical features of enteric fever in the diagnosis of enteric fever. The aim of the study was analysis of clinical features and also proposed a clinical diagnostic criterion of enteric fever among adult in Bangladesh. This cross-sectional comparative study was performed among which of fifty confirmed enteric fever and hundred non enteric febrile adult patients in Bangabandhu Sheikh Mujib Medical University, Dhaka, Bangladesh from January 2015 to December 2015. Purposive sampling technique was implied for convenience of the study. In this study, history of step ladder fever, diarrhoea and relative bradycardia, ceacal gurgle, abdominal distension were proved to be powerful markers of enteric fever with high specificity (100.0%, 90.0%, 95.0%, 92.0% and 95.0% respectively). Tender right iliac fossa (RIF) and coated tongue, hepatomegaly were moderately powerful with 86.0%, 88.0%, 89.0% specificity respectively. Positive predictive value (PPV) was highest for step ladder fever (100%) and negative predictive value (NPV) was highest for headache (92.5%). Highest sensitivity, PPV and NPV were found for relative bradycardia and tender RIF but most of the signs had good specificity. Regarding accuracy it was highest for step ladder fever (91.3%), relative bradycardia (94%), tender RIF (87%), coated tongue (82%) and splenomegaly (84%). Therefore, a clinical diagnostic criterion was submitted with diagnostic accuracy more than 70% were taken into deliberation. The Major criteria were considered step ladder fever, relative bradycardia, tender RIF with diagnostic accuracy 91.0%, 94.0% and 87.0% respectively. Minor criteria included splenomegaly, diarrhoea, coated tongue, ceacal gurgle, chills with diagnostic accuracy 85.0%, 85.0%, 82.0%, 76.0%, 72.0% respectively and after amalgamation of various major and minor criteria a final diagnostic criterion was submitted having accuracy more than 60.0%. In conclusion the clinical profile of enteric fever in culture proven patients with a view to highlight the predictive value of those features which would help general practitioners in the diagnosis and empiric treatment.

Challenges in the Management of Multiple Splenic Abscesses caused by Extensively Drug-resistant (XDR) Salmonella Typhi

Extensively drug-resistant (XDR) typhoid emerged in Hyderabad, Pakistan in 2016. It spread regionally and globally due to fast travelling. An immuno-competent young male referred by general practitioner, was diagnosed and managed as XDR salmonella typhi with multiple splenic abscesses. We faced challenges in its management, like little suspicion of potentially lethal disease; non-availability of evidence-based medicine and further delay in diagnosis as he was already on antibiotics therapy. Patient was diagnosed by radiology and blood cultures. In our case, option of conservative treatment with sensitive antibiotics (azithromycin and meropenem) was successful, though with increased hospital stay. There is no data on treatment duration and choice between two sensitive antibiotics or both in combination. In the present situation, sensitisation of clinicians to salmonella drug resistance, rational use of antibiotics and prompt public health awareness is the need of the day, especially in endemic areas. KEY WORDS: Extensively drug-resistant (XDR) typhoid,Splenic abscesses, Azithromycin, Meropenem.

Enteric fever presenting as catatonia syndrome - Case report

Enteric or typhoid fever is an emerging tropical infectious disease and a global public health problem with a documented spectrum of neuro-psychiatric manifestations especially from endemic countries. Although neuro-psychiatric manifestations are reported in nearly 50-75% of patients at any phase of enteric fever, the chance of their misdiagnosis and deferred diagnosis of the prime illness is quite common. Atypical symptoms are commonly attributed to be a part of 'typhoid toxaemia', the acute febrile phase of the illness. We report a case of young male presenting with catatonia in the aftermath of such.

Prevalence of Enteric Fever Pathogens Isolated from Blood Culture at a Tertiary Care Centre

INTRODUCTION

Typhoid fever and paratyphoid fever commonly called as enteric fever is a life-threatening illness caused by Salmonella serotype Typhi and Salmonella serotype Paratyphi, respectively. It is a major public health issue in underdeveloped and developing countries. The aim of the study is to find out the prevalence of enteric fever pathogens in blood culture of patients attending a tertiary care centre.

METHODS

A descriptive cross-sectional study was conducted in 3483 blood samples of patients attending a tertiary care centre, with the history and symptoms suspicious of enteric fever during one year period from mid-September 2019 to mid-September 2020 after ethical approval from the institutional review committee. Isolates were identified by standard microbiological methods and tested for in vitro antibiotic susceptibility by modified kirby-bauer disc diffusion method. The obtained data was entered and analyzed in WHONET 5.6 program, point estimate at 95% was calculated along with frequency and proportion for binary data.

RESULTS

In our study, enteric fever pathogens were isolated from 18 (0.51%) blood samples. Out of which, Salmonella Paratyphi A was isolated from 10 (8.19%) and Salmonella Typhi was isolated from 8 (6.55%) blood samples. Other serotypes were not isolated. Antimicrobial susceptibility test showed that salmonella species that was isolated were sensitive to most of the drugs.

CONCLUSIONS

Prevalence of enteric fever pathogens was lesser compared to other studies. Varying degrees of antibiotic resistance among isolated enteric fever pathogens necessitates continuous surveillance of the susceptibility patterns. Prudent use of antimicrobials, active infection control practices and stringent antibiotic policy should be implemented to prevent emergence of antibiotic resistance and future outbreaks.

Human Genetic Variation Influences Enteric Fever Progression

In the 21st century, enteric fever is still causing a significant number of mortalities, especially in high-risk regions of the world. Genetic studies involving the genome and transcriptome have revealed a broad set of candidate genetic polymorphisms associated with susceptibility to and the severity of enteric fever. This review attempted to explain and discuss the past and the most recent findings on human genetic variants affecting the progression of Salmonella typhoidal species infection, particularly toll-like receptor (TLR) 4, TLR5, interleukin (IL-) 4, natural resistance-associated macrophage protein 1 (NRAMP1), VAC14, PARK2/PACRG, cystic fibrosis transmembrane conductance regulator (CFTR), major-histocompatibility-complex (MHC) class II and class III. These polymorphisms on disease susceptibility or progression in patients could be related to multiple mechanisms in eliminating both intracellular and extracellular Salmonella typhoidal species. Here, we also highlighted the limitations in the studies reported, which led to inconclusive results in association studies. Nevertheless, the knowledge obtained through this review may shed some light on the development of risk prediction tools, novel therapies as well as strategies towards developing a personalised typhoid vaccine.

Late-onset sepsis due to Salmonella Typhi in a preterm infant in a French neonatal unit

We report a case of late-onset sepsis caused by Salmonella Typhi in a one-month old preterm infant hospitalised in our neonatal unit. An investigation of the index case was undertaken to identify the source of contamination. The patient made a complete recovery.

Predictive evaluation of pediatric patients based on their typhoid fever status using linear discriminant model

Epidemiologic studies have established a relationship between pediatric patients and typhoid fever infection. This study was carried out to ascertain if specific hematological measurements of the pediatric patients discriminate between their positive and negative status to typhoid infection and to produce a rule for classifying other pediatric patients. Discriminant analysis was applied to predict the probability of a specific categorical outcome based on several explanatory variables (predictors). This study analyzed the differentiation between two hundred pediatric patients attending Landmark University Medical Centre based on their typhoid fever status. The hematological parameters considered were Packed Cell Volume, White Blood Cell count; Neutrophil, Erythrocyte level, Hemoglobin and Platelet count, Assay of samples were performed using standard procedures. Fisher's Linear Discriminant Method was used for classification of variables in this study. With the use of the Fisher's Linear Discrimination method for classification of the obtained data, a minimum value of -0.0067 was obtained implying that any new pediatric patient with a discriminant score above -0.0067 would be diagnosed to be typhoid negative; otherwise, they would be classified as typhoid positive pediatric patients. The efficiency of this method of classification was tested using two approaches; Retribution estimate approach and leaving-one out approach which showed a prevalence rate of typhoid positive patients at 75.8% and 74.7% respectively. This data analysis hypotheses that typhoid fever is highly endemic amongst our study subjects. A point-of-care diagnosis with a strong positive predictive value, which improves pediatric enteric fever diagnosis, is strongly advocated.

Diagnostic Value of Clinical Features to Distinguish Enteric Fever From Other Febrile Illnesses in Bangladesh, Nepal, and Pakistan

BACKGROUND

Enteric fever, a bacterial infection caused by Salmonella enterica serotypes Typhi and Paratyphi A, frequently presents as a nonlocalizing febrile illness that is difficult to distinguish from other infectious causes of fever. Blood culture is not widely available in endemic settings and, even when available, results can take up to 5 days. We evaluated the diagnostic performance of clinical features, including both reported symptoms and clinical signs, of enteric fever among patients participating in the Surveillance for Enteric Fever in Asia Project (SEAP), a 3-year surveillance study in Bangladesh, Nepal, and Pakistan.

METHODS

Outpatients presenting with ≥3 consecutive days of reported fever and inpatients with clinically suspected enteric fever from all 6 SEAP study hospitals were eligible to participate. We evaluated the diagnostic performance of select clinical features against blood culture results among outpatients using mixed-effect regression models with a random effect for study site hospital. We also compared the clinical features of S. Typhi to S. Paratyphi A among both outpatients and inpatients.

RESULTS

We enrolled 20 899 outpatients, of whom 2116 (10.1%) had positive blood cultures for S. Typhi and 297 (1.4%) had positive cultures for S. Paratyphi A. The sensitivity of absence of cough was the highest among all evaluated features, at 65.5% (95% confidence interval [CI], 55.0-74.7), followed by measured fever at presentation at 59.0% (95% CI, 51.6-65.9) and being unable to complete normal activities for 3 or more days at 51.0% (95% CI, 23.8-77.6). A combined case definition of 3 or more consecutive days of reported fever and 1 or more of the following (a) either the absence of cough, (b) fever at presentation, or (c) 3 or more consecutive days of being unable to conduct usual activity--yielded a sensitivity of 94.6% (95% CI, 93.4-95.5) and specificity of 13.6% (95% CI, 9.8-17.5).

CONCLUSIONS

Clinical features do not accurately distinguish blood culture-confirmed enteric fever from other febrile syndromes. Rapid, affordable, and accurate diagnostics are urgently needed, particularly in settings with limited or no blood culture capacity.

Utilization of Blood Culture in South Asia for the Diagnosis and Treatment of Febrile Illness

BACKGROUND

Blood culture is the current standard for diagnosing bacteremic illnesses, yet it is not clear how physicians in many low- and middle-income countries utilize blood culture for diagnostic purposes and to inform treatment decisions.

METHODS

We screened suspected enteric fever cases from 6 hospitals in Bangladesh, Nepal, and Pakistan, and enrolled patients if blood culture was prescribed by the treating physician. We used generalized additive regression models to analyze the probability of receiving blood culture by age, and linear regression models to analyze changes by month to the proportion of febrile cases prescribed a blood culture compared with the burden of febrile illness, stratified by hospital. We used logistic regression to analyze predictors for receiving antibiotics empirically. We descriptively reviewed changes in antibiotic therapy by susceptibility patterns and coverage, stratified by country.

RESULTS

We screened 30 809 outpatients resulting in 1819 enteric fever cases; 1935 additional cases were enrolled from other hospital locations. Younger outpatients were less likely to receive a blood culture. The association between the number of febrile outpatients and the proportion prescribed blood culture varied by hospital. Antibiotics prescribed empirically were associated with severity and provisional diagnoses, but 31% (1147/3754) of enteric fever cases were not covered by initial therapy; this was highest in Pakistan (50%) as many isolates were resistant to cephalosporins, which were commonly prescribed empirically.

CONCLUSIONS

Understanding hospital-level communication between laboratories and physicians may improve patient care and timeliness of appropriate antibiotics, which is important considering the rise of antimicrobial resistance.

Evaluation of a Rapid Point-of-Care Multiplex Immunochromatographic Assay for the Diagnosis of Enteric Fever

There is a critical need for an improved rapid diagnostic for enteric fever. We have previously demonstrated that serum IgA responses targeting Salmonella enterica serovar Typhi hemolysin E (HlyE) and lipopolysaccharide (LPS) are able to discriminate patients with acute typhoid from healthy controls in areas where enteric fever is endemic (healthy endemic controls) and from patients with other bacterial infections. We now have data demonstrating that IgA antibody responses against these antigens also work well for identifying patients with acute S. Paratyphi A infection. To develop a test for acute enteric fever detection, we have adapted a point-of-care immunochromatographic dual-path platform technology (DPP), which improves on the traditional lateral flow technology by using separate sample and conjugate paths and a compact, portable reader, resulting in diagnostics with higher sensitivity and multiplexing abilities. In this analysis, we have compared our standard enzyme-linked immunosorbent assay (ELISA) method to the DPP method in detecting acute phase plasma/serum anti-HlyE and anti-LPS IgA antibodies in a cohort of patients with culture-confirmed S. Typhi (n = 30) and Paratyphi A infection (n = 20), healthy endemic controls (n = 25), and febrile endemic controls (n = 25). We found that the DPP measurements highly correlated with ELISA results, and both antigens had an area under the curve (AUC) of 0.98 (sensitivity of 92%, specificity of 94%) with all controls and an AUC of 0.98 (sensitivity of 90%, specificity of 96%) with febrile endemic controls. Our results suggest that the point-of-care DPP Typhoid System has high diagnostic accuracy for the rapid detection of enteric fever and warrants further evaluation.IMPORTANCE Enteric fever remains a significant global problem, and control programs are significantly limited by the lack of an optimal assay for identifying individuals with acute infection. This is especially critical considering the recently released World Health Organization (WHO) position paper endorsing the role of the typhoid conjugate vaccine in communities where enteric fever is endemic. A reliable diagnostic test is needed to assess and evaluate typhoid intervention strategies and determine which high-burden areas may benefit most from a vaccine intervention. Our collaborative team has developed and evaluated a point-of-care serodiagnostic assay based on detection of anti-HlyE and LPS IgA. Our finding of the high diagnostic accuracy of the DPP Typhoid System for the rapid detection of enteric fever has the potential to have significant public health impact by allowing for improved surveillance and for control and prevention programs in areas with limited laboratory capacity.

Subsultus Tendinum in a Child with Typhoid Fever

A 5-year-old male child with blood culture confirmed typhoid fever presented with twitching over the left scapular region. Contrast computerized tomography and electroencephalogram were normal. Following treatment with azithromycin and clonazepam, the twitching subsided. Subsultus tendinum, a rare neurological complication of typhoid fever, resolves spontaneously with treatment.

Management of acute febrile diseases in limited resource settings: a case-based approach

There is a massive burden of acute febrile diseases during the post-monsoon season in tropical countries. Despite this, there is a lack of clarity amongst the primary care physicians and travel medicine experts on how to approach such patients in a syndromic fashion. In this review, the authors summarize a case-based approach in the management of acute febrile diseases.