Neuropsychiatric manifestations of typhoid fever in 959 patients

Typhoid fever in children in Goroka, Papua New Guinea

BACKGROUND

Typhoid is endemic in many low-income countries, including in Papua New Guinea. This study aimed to describe the burden and clinical features of typhoid in children in a provincial hospital, to describe environmental conditions that lead to typhoid, and to document the antibiotic sensitivity of Salmonella spp. in the Eastern Highlands Province.

METHODS

A combined retrospective and prospective study of children admitted to with clinical features of typhoid to the Goroka Hospital throughout 2022.

RESULTS

The study included 98 children, of which 54% were female. The median age was 8 (IQR 5-10.6) years. Over 60% of the patients were from Goroka District, the peri-urban area encompassing the town and surrounds. Ninety-four percent (92) of the patients used a pit latrine as a toilet and only 28% had access to treated water. Neuropsychiatric symptoms were common (60%), as was leukopenia (48%), thrombocytopenia (52%) and anaemia (42%). Thirty-seven patients had positive blood cultures for Salmonella typhi; all isolates were sensitive to third-generation cephalosporins, pefloxacin, ampicillin, trimethoprim and sulfamethoxazole, and only 54% sensitive to chloramphenicol. The median duration of hospitalisation was 6 days (IQR). There were no deaths.

CONCLUSION

Prompt public health actions are needed to reduce the burden of typhoid infection in the Papua New Guinea. The conjugate typhoid vaccine should be considered in the highlands region, where typhoid is most endemic.

Overview of management of infection-related movement disorders with focus on specific-infections

Infections are important treatable causes of secondary movement disorders (MD) that can have heterogeneous presentations. According to various studies, infection-related movement disorders (IRMD) account for around 10-20% of secondary MD. Certain infections have a predilection for causing various MD, and some MD phenomenologies, such as acute cerebellar ataxia and opsoclonus-myoclonus-ataxia syndromes (OMAS), suggest a strong possibility of an underlying infectious cause. The underlying pathophysiology is multifaceted, including direct neuronal damage due to neurotropism, granulomas, abscesses causing structural damage, and inflammatory and autoimmune responses triggered by infections. Understanding the prevalence, spectrum, and pattern of these IRMD and common infections that are responsible helps in early diagnosis, and instituting appropriate, timely treatment, thereby improving the overall prognosis and avoiding unnecessary investigations. In this review, we aim to provide a brief overview of common infections associated with MD, common clinical presentations of IRMD, their underlying pathophysiology, and overall approach to their treatment, with a focus on specific treatments of prevalent and treatable IRMD.

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.

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.

On-treatment improvement of an emerging psychosomatic depressive disorder among salmonella carriers: a multicenter experience from Egypt

Background

As physicians in a referral hospital, we observed the association between history of enteric fever and somatic disorders associated with low mood. At the Al-Hussein University Hospital, Cairo and the National Liver Institute Hospital, Menoufia, we receive patients from all over Egypt, including rural areas where enteric fever is endemic.

Aim

Here in, 60 Egyptian patients referred to us for evaluation of different somatic disorders are reported.

Methods

After extensive evaluations, the patients' symptoms were function-related. Also, their typhoid carrier states were documented, and the severity of depression using Hamilton-D (HAM-D) questionnaire was evaluated and recorded. All patients were treated with ceftriaxone, 2 gm, IV, daily for 15 days. The clinical evaluation and Hamilton score were reassessed at the end of the treatment and 6 weeks thereafter. The patients did not receive any anti-depressant nor anti-anxiety treatment during their course. Typhoid carrier was defined by documenting the history of typhoid fever that was diagnosed by culturing the Salmonella species, and not by serology, isolated from stool culture along with febrile condition, plus the absence of fever in the past 3 weeks. The Widal test was not accepted as a criterion for enrollment.

Results

Patients showed clinically significant improvement in the somatic complaints, and their HAM-D score immediately post-treatment that was consolidated for 6 weeks post-treatment completion.

Conclusion

In this study, the typhoid carrier was associated with the psychosomatic depression that improved by antibiotic therapy.

Parkinson's disease in Nigeria: A review of published studies and recommendations for future research

Parkinson's disease (PD) affects 1-2% of individuals above 60 years amounting to over 7 million people worldwide. Thus, PD has become an important contributor to the neurological disease burden. Nigeria is the most populous country in Africa, and alarmingly, approximately 5.25 million Nigerians are above 65 years and are therefore at risk for developing PD. We carried out a critical review of published literature on PD in Nigeria to summarize the findings and to evaluate gaps in knowledge. Seven electronic databases were searched for studies published in English before 18th July 2018. Search terms were ["Parkinson's disease" OR "Parkinson disease" OR "parkinsonian disorders" OR "Parkinsonism"] AND "Nigeria". A total of 44 articles (including eight reviews) published since 1969 were identified and reviewed. Amongst the original research articles, most (23) were on PD symptoms or prevalence. There were only two studies on genetics and two on environmental factors. The estimated crude prevalence of PD in Nigeria was lower (10-249/100 000) compared to studies published in Europe (65.6-12 500/100 000). Our findings suggest that PD is under-diagnosed in Nigeria. Possible environmental risk factors identified include blacksmithing and well-water contaminated with trace metals. Given the rising numbers of the ageing population in Nigeria, more studies to evaluate the prevalence and causes of PD in this country are urgently needed. To this end, more funding, resources and a workforce of well-trained neurologists and scientists are essential to manage the impending health burden of PD and related disorders in this country.

Salmonella Typhi genomics: envisaging the future of typhoid eradication

Next-generation whole-genome sequencing has revolutionised the study of infectious diseases in recent years. The availability of genome sequences and its understanding have transformed the field of molecular microbiology, epidemiology, infection treatments and vaccine developments. We review the key findings of the publicly accessible genomes of Salmonella enterica serovar Typhi since the first complete genome to the most recent release of thousands of Salmonella Typhi genomes, which remarkably shape the genomic research of S. Typhi and other pathogens. Important new insights acquired from the genome sequencing of S. Typhi, pertaining to genomic variations, evolution, population structure, antibiotic resistance, virulence, pathogenesis, disease surveillance/investigation and disease control are discussed. As the numbers of sequenced genomes are increasing at an unprecedented rate, fine variations in the gene pool of S. Typhi are captured in high resolution, allowing deeper understanding of the pathogen's evolutionary trends and its pathogenesis, paving the way to bringing us closer to eradication of typhoid through effective vaccine/treatment development.

Recurrent mania consequent to quinolones exposure: A case report and review of literature

Antibiotics are the one of the most commonly used group, of drugs, in general medical and surgical practice. The quinolone antibiotics can lead to a range of adverse neuropsychiatric effects with most of the reports due to ciprofloxacin and ofloxacin. Here, we report an interesting and rarely described psychiatric manifestation of recurrent mania following the use of quinolone antibiotics, and briefly review the available literature.

Guillain-Barré syndrome: causes, immunopathogenic mechanisms and treatment

INTRODUCTION

Guillain-Barré syndrome is a rare disease representing the most frequent cause of acute flaccid symmetrical weakness of the limbs and areflexia usually reaching its peak within a month. The etiology and pathogenesis remain largely enigmatic and the syndrome results in death or severe disability in 9-17% of cases despite immunotherapy. Areas covered: In terms of etiology, Guillain-Barré syndrome is linked to Campylobacter infection but less than 0.1% of infections result in the syndrome. In terms of pathogenesis, activated macrophages and T cells and serum antibodies against gangliosides are observed but their significance is unclear. Expert commentary: Guillain-Barré syndrome is a heterogeneous condition with numerous subtypes and recent data point towards the role of ganglioside epitopes by immunohistochemical methods. Ultimately, the syndrome results from a permissive genetic background on which environmental factors, including infections, vaccination and the influence of aging, lead to disease.

Approach to clinical syndrome of jaundice and encephalopathy in tropics

A large number of patients present with jaundice and encephalopathy in tropical country like India and acute liver failure is the usual cause. Clinical presentation like ALF is also a complication of many tropical infections, and these conditions may mimic ALF but may have subtle differences from ALF. Moreover, what hepatologists see as acute liver failure in tropics is different from what is commonly described in Western Textbooks. Paracetamol overdose, which is possibly the commonest cause of ALF in UK and USA, is hardly ever seen in India. Most common etiology here is viral hepatitis (hepatitis E > hepatitis B> hepatitis A). Apart from ALF, one may also come across subacute hepatic failure (SAHF) as well as acute-on-chronic liver failure (ACLF) due to viral hepatitis. Interestingly, a host of other conditions can mimic ALF because clinical presentation in these conditions can be dominated by jaundice and encephalopathy. Malarial hepatopathy is possibly the best-known condition out of these and is not an uncommon manifestation of severe malaria. A similar presentation can also be seen in other common infections in tropics such as dengue fever, typhoid fever, leptospirosis, scrub typhus, amoebic liver abscesses, tuberculosis and other bacterial and fungal infections with or without human immunodeficiency virus (HIV) related disease. In many of these conditions, liver failure may not be underlying pathophysiology. Some pregnancy related liver diseases could also present with jaundice and encephalopathy. This review summarizes the commonly seen presentations in tropical country like India, where jaundice and encephalopathy dominate the clinical picture.

Psychosis in paratyphoid fever - a case report from Australia

OBJECTIVE

Neuropsychiatric presentation in paratyphoid fever is not a well-known entity. In countries such as Australia, where the prevalence of enteric fever is one of the lowest, this presentation seems to be unlikely.

METHOD

We present a case that demonstrates the importance of considering this possibility in Australian context in returned travellers.

RESULTS

A young male, who recently returned to Australia from his home country in South East Asia, presented with abnormal behaviour in the context of febrile illness. His behaviour was characterised by grandiosity, aggression, hallucinatory behaviour and paranoia, along with disturbed biological functions. Detailed inpatient assessment revealed him to be suffering from Salmonella Paratyphi A infection and psychotic illness because of his general medical condition. Although his fever and inflammatory markers responded to antibiotics, antipsychotics were required for treatment of his mental health problems.

CONCLUSION

This case demonstrates that paratyphoid fever, which is considered to be a less common variant of enteric fever, can present with neuropsychiatric manifestations.

Infectious and noninfectious triggers in Guillain-Barré syndrome

Guillain-Barré syndrome (GBS) is the commonest cause of acquired flaccid paralysis in the world and regarded by many as the prototype for postinfectious autoimmunity. Here the authors consider both infectious and noninfectious triggers of GBS and determine where possible what immunological mechanisms may account for this association. In approximately two-thirds of cases, an infectious trigger is reported in the weeks that lead up to disease onset, indicating that the host's response to infection must play an important role in disease pathogenesis. The most frequently identified bacteria, Campylobacter jejuni, through a process known as molecular mimicry, has been shown to induce cross-reactive anti-ganglioside antibodies, which can lead to the development of axonal-type GBS in some patients. Whether this paradigm can be extended to other infectious organisms or vaccines remains an important area of research and has public health implications. GBS has also been reported rarely in patients with underlying systemic diseases and immunocompromised states and although the exact mechanism is yet to be established, increased susceptibility to known infectious triggers should be considered most likely.

Neurologic manifestations associated with an outbreak of typhoid fever, Malawi--Mozambique, 2009: an epidemiologic investigation

Background

The bacterium Salmonella enterica serovar Typhi causes typhoid fever, which is typically associated with fever and abdominal pain. An outbreak of typhoid fever in Malawi-Mozambique in 2009 was notable for a high proportion of neurologic illness.

Objective

Describe neurologic features complicating typhoid fever during an outbreak in Malawi-Mozambique

Methods

Persons meeting a clinical case definition were identified through surveillance, with laboratory confirmation of typhoid by antibody testing or blood/stool culture. We gathered demographic and clinical information, examined patients, and evaluated a subset of patients 11 months after onset. A sample of persons with and without neurologic signs was tested for vitamin B6 and B12 levels and urinary thiocyanate.

Results

Between March – November 2009, 303 cases of typhoid fever were identified. Forty (13%) persons had objective neurologic findings, including 14 confirmed by culture/serology; 27 (68%) were hospitalized, and 5 (13%) died. Seventeen (43%) had a constellation of upper motor neuron findings, including hyperreflexia, spasticity, or sustained ankle clonus. Other neurologic features included ataxia (22, 55%), parkinsonism (8, 20%), and tremors (4, 10%). Brain MRI of 3 (ages 5, 7, and 18 years) demonstrated cerebral atrophy but no other abnormalities. Of 13 patients re-evaluated 11 months later, 11 recovered completely, and 2 had persistent hyperreflexia and ataxia. Vitamin B6 levels were markedly low in typhoid fever patients both with and without neurologic signs.

Conclusions

Neurologic signs may complicate typhoid fever, and the diagnosis should be considered in persons with acute febrile neurologic illness in endemic areas.

Consumption of pesticide-treated wheat seed by a rural population in Malawi

An outbreak of typhoid fever in rural Malawi triggered an investigation by the Malawi Ministry of Health and the Centers for Disease Control and Prevention in July 2009. During the investigation, villagers were directly consuming washed, donated, pesticide-treated wheat seed meant for planting. The objective of this study was to evaluate the potential for pesticide exposure and health risk in the outbreak community. A sample of unwashed (1430 g) and washed (759 g) wheat seed donated for planting, but which would have been directly consumed, was tested for 365 pesticides. Results were compared with each other (percentage change), the US Environmental Protection Agency's (EPA) health guidance values and estimated daily exposures were compared with their Reference dose (RfD). Unwashed and washed seed samples contained, respectively: carboxin, 244 and 57 p.p.m.; pirimiphos methyl, 8.18 and 8.56 p.p.m.; total permethrin, 3.62 and 3.27 p.p.m.; and carbaryl, 0.057 and 0.025 p.p.m.. Percentage change calculations (unwashed to washed) were as follows: carboxin, -76.6%; pirimiphos methyl, +4.6%; total permethrin, -9.7%; and carbaryl -56.1%. Only carboxin and total permethrin concentration among washed seed samples exceeded US EPA health guidance values (285 × and seven times, respectively). Adult estimated exposure scenarios (1 kg seed) exceeded the RfD for carboxin (8 × ) and pirimiphos methyl (12 × ). Adult villagers weighing 70 kg would have to consume 0.123, 0.082, 1.06, and 280 kg of washed seed daily to exceed the RfD for carboxin, pirimiphos methyl, permethrins, and carbaryl, respectively. Carboxin, pirimiphos methyl, permethrins, and carbaryl were detected in both unwashed and washed samples of seed. Carboxin, total permethrin, and carbaryl concentration were partially reduced by washing. Health risks from chronic exposure to carboxin and pirimiphos methyl in these amounts are unclear. The extent of this practice among food insecure communities receiving relief seeds and resultant health impact needs further study.

Factors associated with encephalopathy in patients with Salmonella enterica serotype Typhi bacteremia presenting to a diarrheal hospital in Dhaka, Bangladesh

To characterize clinical correlates of typhoid fever-associated encephalopathy, we performed a retrospective chart review of patients with Salmonella enterica serotype Typhi bacteremia who were hospitalized at the International Centre for Diarrhoeal Disease Research, Bangladesh, from February of 2009 to June of 2011. Of 207 patients bacteremic with Salmonella Typhi who were ≥ 5 years of age, we identified 43 (21%) patients with encephalopathy. Univariate analysis revealed that patients with encephalopathy more often presented at ages of 10-24 years and had severe dehydration, low oxygen saturation, high respiratory rate, low leukocyte count, low platelet count, and Widal flagellar H agglutinin (TH) titer ≥ 1:640 compared with typhoid patients without encephalopathy. Multivariate analysis using logistic regression showed that age, dehydration, leukocyte count, and Widal TH titer were independently associated with encephalopathy. Our findings suggest that age, severity of disease, and immune responses are associated with encephalopathy during Salmonella Typhi bacteremia, perhaps reflecting the impact of prominent inflammatory responses.

Multidrug-resistant typhoid fever with neurologic findings on the Malawi-Mozambique border

BACKGROUND

Salmonella enterica serovar Typhi causes an estimated 22 million cases of typhoid fever and 216 000 deaths annually worldwide. We investigated an outbreak of unexplained febrile illnesses with neurologic findings, determined to be typhoid fever, along the Malawi-Mozambique border.

METHODS

The investigation included active surveillance, interviews, examinations of ill and convalescent persons, medical chart reviews, and laboratory testing. Classification as a suspected case required fever and ≥1 other finding (eg, headache or abdominal pain); a probable case required fever and a positive rapid immunoglobulin M antibody test for typhoid (TUBEX TF); a confirmed case required isolation of Salmonella Typhi from blood or stool. Isolates underwent antimicrobial susceptibility testing and subtyping by pulsed-field gel electrophoresis (PFGE).

RESULTS

We identified 303 cases from 18 villages with onset during March-November 2009; 214 were suspected, 43 were probable, and 46 were confirmed cases. Forty patients presented with focal neurologic abnormalities, including a constellation of upper motor neuron signs (n = 19), ataxia (n = 22), and parkinsonism (n = 8). Eleven patients died. All 42 isolates tested were resistant to ampicillin, chloramphenicol, and trimethoprim-sulfamethoxazole; 4 were also resistant to nalidixic acid. Thirty-five of 42 isolates were indistinguishable by PFGE.

CONCLUSIONS

The unusual neurologic manifestations posed a diagnostic challenge that was resolved through rapid typhoid antibody testing in the field and subsequent blood culture confirmation in the Malawi national reference laboratory. Extending laboratory diagnostic capacity, including blood culture, to populations at risk for typhoid fever in Africa will improve outbreak detection, response, and clinical treatment.

Isolated cerebellar ataxia: an early neurological complication of enteric fever

Enteric fever is associated with a variety of clinical presentations and complications. Although central nervous system involvement is not uncommon in enteric fever, acute cerebellar ataxia as a presenting feature is rare. A 7-year-old boy with enteric fever who presented with acute cerebellar ataxia is reported.

Salmonella meningitis in an adult with type B viral hepatitis and an incidental schwannoma

Salmonella meningitis is an unusual complication of Salmonella sepsis that occurs almost exclusively in infants and young children. Cases that do occur in adults are associated with a high morbidity and mortality. The present study concerns a rare case of Salmonella meningitis, the first to be reported in Qatar, in a previously healthy young adult man who was admitted with fever, headache and nuchal rigidity. Cerebrospinal fluid (CSF) culture produced Salmonella paratyphi A, although cultures of blood were negative. The patient was admitted to the medical intensive care unit (MICU) and assisted with mechanical ventilation for 1 week, then transferred to the medical ward where he exhibited progressive improvement on treatment with meropenam for 3 weeks. The patient was found to have an incidental schwannoma causing right-sided hydronephrosis, and hydroureter, treated with double J stent insertion. He was discharged in good condition without any neurological sequelae.

Fever, a blue hand, and abducens nerve paralysis in a returning traveler

Fever, caused by Salmonella typhi, is the cause of significant morbidity worldwide. Extraintestinal manifestations of typhoid fever can confuse clinicians in Western countries, delaying diagnosis. We present an extraordinary case of typhoid fever, manifesting as hand cyanosis as well as abducens nerve paresis, all of which promptly resolved with antibiotics.

Transient dysautonomia and cerebellitis in childhood enteric fever

A case of childhood enteric fever complicated by transient dysautonomia and cerebellitis is reported. The child was treated with intravenous antibiotics, and the complications were managed conservatively. Dysautonomia and cerebellitis resolved by day 5 and day 8 after admission, respectively. Results of a neurologic examination at the end of 6 months were normal. Dysautonomia complicating the course of childhood enteric fever is previously unreported.

Guillain-Barré syndrome associated with Salmonella paratyphi A

A 31-year-old Nepali man was admitted to the intensive care unit with a 3-day history of fever associated with four-limb weakness, followed by difficulty in swallowing. The patient came from Nepal 20 days before admission. On examination the patient was conscious and appeared ill, with a temperature of 38.0 degrees C. His four limbs were weak (grades 2-3) and he was areflexic with mild facial weakness and absent gag reflex. Brain CT and MRI were normal. Cerebrospinal fluid analysis showed high protein. A neurophysiologic study showed data consistent with motor axonal polyradiculopathy. The patient was diagnosed with Guillain-Barré syndrome (GBS), and intravenous immunoglobulin (0.4 g/kg day for 5 days) was administered. On the third hospitalization day, the patient developed respiratory failure for which he was intubated and mechanically ventilated. On the same day, blood samples grew Salmonella paratyphi A (S. paratyphi A), which was sensitive to ceftriaxone. The patient was then diagnosed with GBS associated with S. paratyphi A, and treated with ceftriaxon (2 g administered intravenously, daily for 10 days). On the eleventh hospitalization day the patient was weaned from ventilator and extubated successfully. Subsequently, the patient improved, his fever subsided, and he regained muscle power satisfactorily.

Confusion in travellers

Acute onset long haul in-flight confusion, restlessness, disorientation and abnormal behaviour in a 24 year old lady who had recent typhoid fever is reported. Confusion in travelers within the context of infections, including typhoid psychosis, and other causes, is discussed to enlighten practitioners on the problem, and ensuing potential medico-legal and ethical issues.

Movement disorders in the tropics

The spectrum of movement disorders in the tropics is different from that seen in the industrialized nations of the west. This is not surprising given the unique combination of environmental and population characteristics in the tropics. Infections seldom encountered in the west such as tuberculous meningitis, typhoid fever, Japanese encephalitis, malaria, trypanosomiasis or cysticercosis are often seen in the tropics and with global patterns of travel and immigration these conditions are becoming more common worldwide. Movement disorders associated with these infections, HIV, slow virus and prion disease are discussed. Taking into account the diverse etiologies of movement disorders in the tropics, movement disorders with a nutritional basis such as the infantile tremor syndrome, seasonal ataxia and tropical ataxic neuropathy, and manganese neurotoxicity are also reviewed. Finally, certain special characteristics of ubiquitous disorders such as Parkinson's disease, and disorders with a genetic basis such as Wilson's disease and spinocerebellar degeneration are described.

Correlates of psychiatric morbidity in typhoid fever in a Nigerian general hospital setting

This study explored factors associated with psychiatric morbidity in typhoid fever in a Nigerian general hospital. Information such as sociodemographic characteristics, symptom manifestations, results of investigations, neuropsychiatric symptoms, outcome and disposal were obtained from the case files of patients admitted for typhoid fever over a period of six years. The patients with psychiatric morbidity conspicuous enough to be documented by the attending physicians-mostly internists-were compared with those with no documented psychiatric morbidity on sociodemographic and clinical indices. Of the 136 cases, 26 (19.1%) had psychiatric morbidity. This included delirium (73.1%), generalized anxiety disorder (3.8%), depressive episode (3.8%), schizophrenia like disorder (3.8%) and monosymptomatic neuropychiatric manifestations such as apathy, hallucinations and irrelevant talking (15.5%). The clinical and sociodemographic indices that were significantly associated with psychiatric morbidity were diarrhea, blood biochemical imbalance and age (P<.05). Adolescents and young adults were more predisposed to developing psychiatric complications. Some factors potentially associated with psychiatric morbidity in typhoid fever have been identified. There is the need to prospectively assess the burden from psychiatric morbidity and identify interventions that may reduce it.

Salmonella hepatitis

Typhoid fever is often associated with abnormal liver biochemical tests, but severe hepatic involvement with a clinical feature of acute hepatitis is a rare complication. There have been more than 150 cases of salmonella hepatitis reported from both developed and developing countries. The documented incidence varies widely from less than 1% to 26% patients with enteric fever. The possible associated factors for development of salmonella hepatitis are virulence of the organisms, delayed treatment and poor general health of the patients. The pathogenesis of severe hepatic involvement in salmonella infection may be multifactorial and includes endotoxin, local inflammatory and/or host immune reactions. Clinical jaundice in salmonella hepatitis usually occurs within the first 2 weeks of the febrile illness. Hepatomegaly and moderate elevation of transaminase levels are common findings. Extreme hepatic dysfunction with hepatic encephalopathy is a rare coexisting complication in salmonella hepatitis. A positive culture for salmonella from blood or stool is essential to differentiate salmonella hepatitis from other causes of acute hepatitis. Hepatic pathology is characterized by the presence of typhoid nodules with marked hyperplasia of reticuloendothelial cells. The prognosis is usually good as salmonella hepatitis responds well to a specific antibiotic therapy and juandice resolves with clinical improvement. The clinical course can be severe with a mortality rate as high as 20%, particularly with delayed treatment or in patients with other complications of salmonella infection. As enteric fever is a common infection, the recognition of salmonella hepatitis is of clinical importance.

The biological basis of malarial disease

In this review we summarise the arguments that inflammatory cytokines, triggered by material released from the parasite at schizogony (malarial toxin), might induce the illness and pathology seen in malaria. These pro-inflammatory cytokines can generate inducible nitric oxide synthase and cause nitric oxide to be released, as can low concentrations of malarial toxin itself provided interferon-gamma, which has only low activity in the absence of malarial toxin, is present. We suggest here that recently described hypermetabolic functions of these mediators provide a much more plausible explanation for malarial hyperlactataemia and hypoglycaemia, the chief prognostic indicators in falciparum malaria, than does hypoxia secondary to mechanical blockage of vessels by sequestering parasites, which is the dominant current theory. We also review the arguments that rationalise, through these mediators, the reversibility of the coma of cerebral malaria. Although not yet tested at a cellular level, the proposal that nitric oxide generated in cerebral vascular walls contributes to this coma continues to gather indirect support. In addition, new evidence incriminating nitric oxide in the mechanism of tolerance to endotoxin rationalises the raised nitric oxide generation seen in malarial tolerance.

Spectrum of neuropsychiatric complications in 791 cases of typhoid fever

Over a 6-year period, we studied 791 patients with multidrug-resistant typhoid fever, of whom 665 individuals (84%) developed neuropsychiatric manifestations. These were: acute confusional state (73%); myelitis (6%); cerebellitis (1%); parkinsonism (1%); acute psychosis (0.6%); meningo-encephalitis (0.5%); encephalitis (0.25%); sensory motor polyneuropathy, polymyositis, acute schizophrenia and bizarre neurological syndromes (0.12% each). Severe parkinsonian rigidity and meningo-encephalitis are associated with significant morbidity but very low mortality (0.5%).

MR findings in cerebellar ataxia after enteric fever

A patient with acute cerebellar ataxia after enteric fever is described. MRI showed multiple hypointense areas in the subcortical areas of the cerebellum on T1-weighted images, and T2-weighted images showed hyperintense lesions in the corresponding areas. Based on these findings, the possible mechanisms of ataxia are discussed.

Ataxia in patients infected with Salmonella typhi phage type D2: clinical, biochemical and immunohistochemical studies

Reversible cerebellar dysfunction has been described in association with typhoid fever by a number of authors. Ataxia and tremors are relatively common manifestations of typhoid fever in Papua New Guinea. A series of 14 patients with typhoid fever and ataxia was compared with non-ataxic typhoid patients. Hyponatraemia and hypoalbuminaemia were common in both groups and more severe in the ataxic group. Hypotension was also more common in the ataxic group. These features may reflect more severe disease. All isolates of Salmonella typhi, from both ataxic and non-ataxic patients, were phage type D2 which is endemic around Port Moresby. Tests for autoantibodies cross-reacting with cerebellar tissue were negative. It is possible that cerebellar dysfunction in typhoid fever is more common in association with phage type D2.

Encephalopathy associated with Salmonella enteritidis infection

A 15-year-old boy who presented with a short history of a diarrhoeal illness associated with encephalopathic features is described. Salmonella enteritidis phage type 4 was cultured from his stool. Although encephalopathy in the absence of CNS infection or electrolyte disturbance is well described in enteric fever, it is very rare in infections with non-typhoidal Salmonella serotypes and has not previously been described in association with S. enteritidis infection.

Further consideration of the clonal nature of Salmonella typhi: evaluation of molecular and clinical characteristics of strains from Indonesia and Peru

We examined envelope protein profiles, chromosomal restriction endonuclease digest patterns, and immune responses to envelope proteins for collections of Salmonella typhi strains isolated in Peru and Indonesia. Only minor differences in envelope protein patterns were apparent among strains. Strains from 7 of 20 Indonesian patients had a distinct chromosomal digest pattern compared with patterns of Peruvian and other Indonesian strains. Strains with this pattern carried the gene for the j flagellar antigen (H1-j); differences in response to envelope proteins of j and d strains were noted on immunoblot analysis. Our data suggest that there are genotypic and phenotypic differences among S. typhi strains. The clinical importance of these differences remains to be fully evaluated; however, in this study it was not possible to show a clear correlation between strain characteristics and disease severity.

Bickerstaff's brainstem encephalitis associated with typhoid fever

A 14 year old boy developed the syndrome of Bickerstaff's brainstem encephalitis during the course of bacteriologically proved typhoid fever. The clinical course and the results of various neurological investigations are detailed. This report adds a further manifestation to the published neuropsychiatric complications of typhoid fever.

Hydrocortisone in chloramphenicol-treated severe typhoid fever in Papua New Guinea

We investigated the effect of hydrocortisone on mortality and complications in chloramphenicol-treated severe typhoid fever (STF) in Goroka, Papua New Guinea. Of 374 culture-positive patients, 146 formed a retrospective comparison group, of whom 41 had STF. Of 228 patients in the intervention group, 58 had STF. Patients without STF had low mortality (2.5%) with standard treatment. In the intervention group, hydrocortisone was used in two dosage schedules, 100 mg for 12 doses (23 patients) and 400 mg for 12 doses (23 patients). There was no difference in mortality between steroid-treated and comparison STF patients (44.8% versus 43.9%) or in complications, and we conclude that moderate doses of steroids are not beneficial in severe typhoid fever.

Proposed link between cytokines, nitric oxide and human cerebral malaria

Nitric oxide (NO), also known as endothelial-derived relaxing factor (EDRF), is generated by a range of cell types including endothelial cells, smooth muscle cells and neurons, and mediates a range of different physiological functions, such as maintenance of vascular tone and neuro-transmission. In this article, Ian Clark, Kirk Rockett and Bill Cowden propose that when vascular generation of NO is particularly high (for example, if local intravascular levels of tumour necrosis factor (TNF) are markedly increased) this mediator could diffuse to nearby neurons, be misinterpreted as being of synaptic origin and thus interfere with orderly neuro-transmission. NO of vascular origin could also, through vasodilation of cerebral vessels, contribute to increased intracranial pressure and thus to certain of the clinical signs seen in cerebral malaria. As well as contributing to cerebral malaria, these phenomena could also lead to the neurological changes observed in certain other systemic diseases.

Haemoglobinuric renal failure and typhoid fever

Three patients with typhoid fever, initially misdiagnosed, developed intravascular haemolysis, disseminated intravascular coagulation, haemoglobinuria and acute renal failure. 2 of the patients were deficient in erythrocyte glucose-6-phosphate dehydrogenase; Plasmodium falciparum was present in the blood of the third. Among the indigenous population of endemic areas, typhoid fever is the likely diagnosis in any pyrexial illness associated with haemoglobinuric renal failure.

Psychiatric manifestations of enteric fever

This is a study of the aetiological and clinical aspects of 50 cases of typhoid fever with psychiatric manifestations in the Sudan. The incidence of psychiatric symptoms was 8%, the clinical picture was one of acute psycho-organic reactions (74%), and in 18% the psychiatric symptoms preceded the onset of the fever. The typhoid infection and, to a lesser degree, susceptible personality seem to be important aetiological factors.