The head nodding syndrome--clinical classification and possible causes

Health Seeking Behaviours among Caretakers of Children with Nodding Syndrome in Pader District - Northern Uganda: A Mixed Methods Study

BACKGROUND

Nodding syndrome is a neurological disorder which had affected about 3000 children with over 170 deaths in northern Uganda by 2012. With limited data on health seeking, the study aimed to assess the health seeking behavior and associated factors among caretakers of children with nodding syndrome in Pader district.

METHODS

A mixed methods cross sectional study was conducted in July 2013 among 249 caretakers of children with nodding syndrome in three sub-counties of Pader. Respondents were consecutively interviewed using semi-structured questionnaires. Eleven key informants were additionally interviewed. We determined the associations of various factors with health care seeking and obtained adjusted odds ratios and 95% confidence intervals using logistic regression model. Quantitative data was analysed using Stata version 12 while qualitative data was analysed manually and quotes reported.

RESULTS

Most caretakers, 78.3% (195/249) sought care first from a health facility, 12.9% (32/249) visited traditional healers and 8.8% (22/249) self-medicated. Of those who sought care from a health facility, 50% sought care after a month. Factors associated with improved care seeking included: Time taken to reach care 1-3 hours; adjusted odds ratio = 6.4 (95% CI = 2.96-14.03), time spent in care above five years; adjusted odds ratio = 12.0 (95% CI: 1.24-117.73) and changed care seeking place; adjusted odds ratio = 17.2 (95% CI: 3.64-81.67).

CONCLUSION/ RECOMMENDATION

Caretakers sought care from multiple places. One in five caretakers still sought care outside a formal health facility. Many respondents who sought care first from health facilities went late, at least one month after symptoms onset. Factors associated with health seeking included distance, duration in treatment and not having changing care provider. There is need for massive sensitization of community to enhance prompt care seeking. More research is needed to elucidate the cause, thus finding the treatment for nodding syndrome, to prevent "wandering in hope".

Reduced plasma concentrations of vitamin B6 and increased plasma concentrations of the neurotoxin 3-hydroxykynurenine are associated with nodding syndrome: a case control study in Gulu and Amuru districts, Northern Uganda

INTRODUCTION

Nodding syndrome was first reported in Uganda in 2003 among internally displaced populations. Risk factors for the syndrome remain unknown. We therefore explored vitamin B6 deficiency and resulting high 3-hydroxykynurenine (3-HK) levels as risk factor for nodding syndrome in Northern Uganda.

METHODS

Case-control study conducted in Gulu and Amuru districts. Cases were children/young adults with nodding syndrome. Healthy children/young adults were recruited as controls from same community as cases. Data on socio-demographic and other risk factors was collected using questionnaires. Whole blood was collected in EDTA tubes for assay of 3-HK and vitamin B6 using sandwich ELISA. Conditional logistic regression model was used to assess associations.

RESULTS

66 cases and 73 controls were studied. Factors associated with nodding syndrome were being positive for 3-HK (AOR=4.50, p=0.013), vitamin B6 concentration below mean (AOR=7.22, P=0.001), child being taken care of by mother only (AOR=5.43, p=0.011), child being taken care of by guardian (AOR=5.90, p=0.019) and child consuming relief food at weaning (AOR=4.05, p=0.021).

CONCLUSION

Having low vitamin B6 concentration which leads to a build up of 3-hydroxykynurenine concentration in cases as a main risk factor. Therefore, cases should be treated with vitamin B6 and community members should be sensitise to ensure adequate dietary intake of vitamin B6 so that the risk of nodding syndrome among children is averted. We encourage future prospective intervention study to be conducted to assess the effect of low vitamin B6 on the development of nodding syndrome via raised 3-HK concentration.

Nodding syndrome: 2015 International Conference Report and Gulu Accord

Nodding syndrome is a pediatric epileptic encephalopathy of apparent environmental origin that was first described in Tanzania, with recent epidemics in South Sudan and Uganda. Following a brief description of the medical geography, setting and case definition of this progressive brain disorder, we report recent advances relating to etiology, diagnosis and treatment described in papers given at the 2nd International Conference on Nodding Syndrome held in July 2015 in Gulu, Uganda. The target audience for this report includes: anthropologists, entomologists, epileptologists, health care workers, helminthologists, medical researchers, neuroepidemiologists, neurologists, neuroscientists, neuropathologists, nurses, nutritional scientists, primary health care physicians, psychiatrists, public health practitioners, toxicologists, and virologists.

The rise and fall of nodding syndrome in public discourse: An analysis of newspaper coverage in Uganda

Nodding syndrome is an unexplained affliction that has affected thousands of children in post-conflict northern Uganda, South Sudan and in Tanzania. This study focuses on the sudden rise of nodding syndrome in the Ugandan public discourse, based on 369 newspaper reports over a timespan of 4.5 years and interviews with journalists, politicians, caretakers and health workers during 15 months of fieldwork in Kitgum district. The news coverage of nodding syndrome follows a non-linear trajectory, increasing at the end of 2011 and declining a year later. Attention is paid to the conceptualization of nodding syndrome in media reports, linked to the formation of public opinion and management of the affliction. Different settings elicit different concepts and it is therefore necessary to contextualize illness and focus on processes of formation.

Risk factors for epilepsy in Bas-Uélé Province, Democratic Republic of the Congo: a case-control study

BACKGROUND

The reason for the high prevalence of epilepsy in onchocerciasis endemic areas remains unknown. The aim of this study was to detect risk factors associated with epilepsy in a region endemic for onchocerciasis.

METHODS

In June 2014, a case-control study was performed in Titule, Bas-Uélé Province in the Democratic Republic of the Congo. Individuals with unprovoked convulsive epilepsy of unknown aetiology were enrolled as cases (n=59). Healthy members of families without cases of epilepsy in the same village were recruited as controls (n=61). A multivariate binomial logistic regression analysis was performed to identify potential risk factors associated with epilepsy. To evaluate the potential protective effect of ivermectin treatment on the development of epilepsy, a nested age-matched case-control study was performed including only those who were eligible for ivermectin treatment in the year before they developed epilepsy.

RESULTS

Suspected onchocerciasis skin lesions were more often present in cases than in controls: 12/41 (29%) vs. 1/56 (2%), respectively (odds ratio (OR) 20.26, 95% confidence interval (CI) 2.42-170; p<0.01). Ivermectin had been taken 7 months earlier in 29/59 (49%) cases and 29/61 (48%) controls. Onchocerca volvulus (OV) DNA was detected by PCR in skin snips in 26/34 cases (76%) and 10/14 controls (71%) (p=0.7), and there was presence of OV IgG4 antibodies in 35/48 (73%) cases and 15/18 (83%) controls (p=0.5). OV DNA was not detected in the cerebrospinal fluid of cases (controls not tested). Both cases and controls reported frequent bites by blackflies (Diptera, Simuliidae). Bathing daily as opposed to less often (OR 16.7, 95% CI 2.2-125.8; p<0.01), bathing between 11 a.m. and 4 p.m. (OR 12.7, 95% CI 1.6-103.7; p=0.02), and washing clothes between 11 a.m. and 4 p.m. (OR 10.9, 95% CI 1.5-77.3; p=0.02) were all independently associated with epilepsy. Blood screening by specific PCR tests for Toxoplasma and Wuchereria bancrofti was negative in all cases and controls. A Loa loa infestation was found in only one case and one control by PCR and Giemsa smear. Antibodies to Taenia solium, Toxocara, and Trypanosoma sp were not detected in any of the participants. In an age-matched case-control analysis, 16/18 (89%) cases had not taken ivermectin the year before they developed epilepsy, compared to 7/18 (39%) controls that same year (p=0.002).

CONCLUSIONS

These data suggest that frequent activities at rivers known to be blackfly breeding sites and a historical lack of ivermectin treatment were risk factors for epilepsy in this onchocerciasis endemic area.

Is nodding syndrome an Onchocerca volvulus-induced neuroinflammatory disorder? Uganda's story of research in understanding the disease

Nodding syndrome is a devastating neurological disorder, mostly affecting children in eastern Africa. An estimated 10000 children are affected. Uganda, one of the most affected countries, set out to systematically investigate the disease and develop interventions for it. On December 21, 2015, the Ministry of Health held a meeting with community leaders from the affected areas to disseminate the results of the investigations made to date. This article summarizes the presentation and shares the story of studies into this peculiar disease. It also shares the results of preliminary studies on its pathogenesis and puts into perspective an upcoming treatment intervention. Clinical and electrophysiological studies have demonstrated nodding syndrome to be a complex epilepsy disorder. A definitive aetiological agent has not been established, but in agreement with other affected countries, a consistent epidemiological association has been demonstrated with infection by Onchocerca volvulus. Preliminary studies of its pathogenesis suggest that nodding syndrome may be a neuroinflammatory disorder, possibly induced by antibodies to O. volvulus cross-reacting with neuron proteins. Histological examination of post-mortem brains has shown some yet to be characterized polarizable material in the majority of specimens. Studies to confirm these observations and a clinical trial are planned for 2016.

Catatonia in Ugandan children with nodding syndrome and effects of treatment with lorazepam: a pilot study

Background

Nodding syndrome (NS) is a severe neuropsychiatric syndrome of an unknown etiology affecting children and adolescents mostly in Eastern Africa. Symptoms of NS and catatonia seem to overlap. We investigated the presence and types of catatonic symptoms in NS and their response to one or two doses of lorazepam, the first-line treatment for catatonia.

Methods

A cross-sectional descriptive study with systematic assessment of catatonia in 33 patients with NS using a modified version of the Bush Francis Catatonia Rating Scale. Sixteen patients met criteria for catatonia and were observed in an open and uncontrolled study to examine the effects of one or two doses of lorazepam in them.

Results

Sixteen of 33 patients with NS had an average of 5 catatonia symptoms and met criteria for catatonia. The highest scores were found for mutism, staring, poor eating/drinking, stupor, and grimacing. Excitement, rigidity, negativism and impulsivity had lower scores. None of the children had echolalia or echopraxia. In 6 children, there was a reduction of more than 50 % in catatonia ratings, representing a positive response to lorazepam. Three out of six children whose catatonia ratings did not change after the first dose, responded after administration of a second double dose. There were no unusual or critical side-effects.

Conclusions

About half of a selected sample of children with NS met criteria for catatonia. Catatonia scores decreased in most patients after one or two doses of lorazepam. Larger, longer, and controlled studies are warranted to assess the prevalence of catatonia in NS and to assess the use of lorazepam in NS through its effects on catatonia.

Trial Registration: ClinicalTrials.gov NCT02462109

Date of formal registration: June 2, 2015

Electronic supplementary material

The online version of this article (doi:10.1186/s13104-015-1805-5) contains supplementary material, which is available to authorized users.

Is the glass half full or half empty? A qualitative exploration on treatment practices and perceived barriers to biomedical care for patients with nodding syndrome in post-conflict northern Uganda

Background

Nodding syndrome has increasingly become an issue of public health concern internationally. The etiology of the disorder is still unknown and there are yet no curative treatments. We explored perceptions about treatment practices and barriers to health seeking for nodding syndrome in Pader and Kitgum districts in northern Uganda in order to provide data necessary for informing policy on treatment adherence and rehabilitations.

Methods

We used focus group discussions and individual interviews to gain deep insights into help-seeking and treatment practices for nodding syndrome. Purposive sampling was used to identify information-rich participants that included village health teams, community members not directly affected with nodding syndrome, district leaders, healthcare professionals, and caregivers of children affected with nodding syndrome. We used qualitative content analysis to analyze data and presented findings under distinct categories and themes.

Results

Caregivers and communities sought care from multiple sources including biomedical facilities, traditional healers, traditional rituals from shrines, and spiritual healing. Nodding syndrome affected children reportedly have showed no enduring improvement with traditional medicines, traditional rituals, and prayers. A substantial minority of participants reported minimal improvements in symptoms of convulsions with use of western medicines. Challenges involved in health seeking included; (1) health system factors e.g. long distances to facilities, frequent unavailability of medicines, few healthcare providers, and long waiting times; (2) contextual and societal challenges e.g. lack of money for transport and medical bills, overburdening nature of the illness that does not allow time for other activities, and practical difficulties involved in transporting the physically deformed and mentally retarded children to the health facilities.

Conclusions

Help-seeking for nodding syndrome is pluralistic and include use of traditional and biomedical practices. Western medicines admittedly showed at least short term control on nodding syndrome symptoms, especially convulsions and led in a few cases to regain of functional abilities. However, multiple barriers hinder health seeking and interfere with adherence to biomedical treatments. Regarding cure, there are hitherto no treatments participants perceive cure nodding syndrome.

Neurophysiological and clinical findings on Nodding Syndrome in 21 South Sudanese children and a review of the literature

PURPOSE

To describe the neurophysiological and clinical features of Nodding Syndrome (NS) in South Sudan.

METHODS

The study was performed at the Epilepsy Service of "Usratuna" sited in Juba, South Sudan. The clinical history of each subject was collected along with an EEG tracing.

RESULTS

Twenty-one children (10 females) were diagnosed with NS. Fifteen (72%) children were classified as Probable NS and six (28%) as Confirmed NS. They ranged in age between 6 and 14 years, and age at seizure onset ranged from 5 to 12 years. All the subjects presented with intellectual disability which was mild in severity in 12 (57%) cases, moderate in seven (33%) cases and severe in two (10%) cases. Interictal EEG was abnormal in 20 subjects. In 18 (85%) subjects, the EEG showed 2-3.5 Hz spike-and-wave discharges often intermingled with sharp waves. Intermittent light stimulation was normal. In 12 (57%) children, interictal abnormalities were activated by hyperventilation. Ictal EEG was obtained in three patients. In all ictal EEGs head nodding episodes came in clusters during hyperventilation. None of the patients achieved good seizure control even if all of them received antiepileptic treatment (carbamazepine alone [43%] or in association with phenobarbitone or phenytoin).

CONCLUSION

This study confirms that NS is an encephalopathy and intellectual disabilities are partially independent of seizure frequency and EEG pathological activity. Based on interictal and ictal EEG patterns and on the experience of other researchers, valproic acid would seem to be the first-choice antiepileptic drug. NS in South Sudan presents with clinical and neurophysiological features which are similar to those described in northern Uganda and more severe than in Tanzania.

Paroxysmal movement disorders

Paroxysmal dyskinesias represent a group of episodic abnormal involuntary movements manifested by recurrent attacks of dystonia, chorea, athetosis, or a combination of these disorders. Paroxysmal kinesigenic dyskinesia, paroxysmal nonkinesigenic dyskinesia, paroxysmal exertion-induced dyskinesia, and paroxysmal hypnogenic dyskinesia are distinguished clinically by precipitating factors, duration and frequency of attacks, and response to medication. Primary paroxysmal dyskinesias are usually autosomal dominant genetic conditions. Secondary paroxysmal dyskinesias can be the symptoms of different neurologic and medical disorders. This review summarizes the updates on etiology, pathophysiology, genetics, clinical presentation, differential diagnosis, and treatment of paroxysmal dyskinesias and other episodic movement disorders.

Nodding syndrome, western Uganda, 1994

Nodding syndrome (NS) is a poorly understood condition, which was delineated in 2008 as a new epilepsy syndrome. So far, confirmed cases of NS have been observed in three circumscribed African areas: southern Tanzania, southern Sudan, and northern Uganda. Case-control studies have provided evidence of an association between NS and infection with Onchocerca volvulus, but the causation of NS is still not fully clarified. We report a case of a 15-year old boy with head nodding seizures and other characteristic features of NS from an onchocerciasis endemic area in western Uganda, with no contiguity to the hitherto known areas. We suggest that the existence of NS should be systematically investigated in other areas.

The enigmatic nodding syndrome outbreak in northern Uganda: an analysis of the disease burden and national response strategies

To date, the cause of nodding syndrome (NS) remains unknown; however, efforts continue to establish risk factors and optimal symptomatic treatments. We documented the burden and national response strategies including involvement of key stakeholders in the management of the NS epidemic in order to inform future interventions against epidemics of undetermined aetiology. Data were collected through semi-structured interviews with selected leaders in the affected districts and at the Ministry of Health, and through review of documents. We participated in and analysed the proceedings of the first international scientific conference on NS held in Kampala in August 2012. We then analysed the chronology of the NS notification and the steps undertaken in the response plan. Over 3000 children have been affected by NS in northern Uganda; with an estimated case fatality of 6.7%. The first cases of NS were reported in 1997 in internally displaced people's camps in Kitgum district; however, response efforts by the Ministry of Health and partners towards understanding the disorder and establish management only commenced in 2009. Key strategies in response to the NS epidemic have included formation of a national and district task forces, development of training manual on NS and training of primary healthcare professionals on case diagnosis and clinical management, establishment of treatment and rehabilitation centres, surveillance and promotion of researches to further inform management of the syndrome.

'These nodding people': Experiences of having a child with nodding syndrome in postconflict Northern Uganda

BACKGROUND

Nodding syndrome, an epidemic epileptic encephalopathy of unknown etiology, has affected an estimated 1834 children in Northern Uganda. Children are being treated symptomatically but inconsistently with antiepileptic drugs.

DESIGN

Ten semistructured interviews with caregivers of affected children and five focus group discussions with 23 relatives, teachers, and religious leaders were conducted to examine the experiences of affected families and communities in Kitgum and Pader districts. The researcher also did participant observation during MoH outreach clinics. Data collection was carried out from July to September 2012, and data were analyzed through inductive thematic analysis.

RESULTS

Nodding syndrome severely affects the children's ability to participate in daily life activities. Daily seizures and physical features such as salivating and stunting make them unable to pass as normal, and mood changes make it difficult for some to interact with others. Caregivers of children with nodding syndrome feel confined to their homes, and economic activities are reduced, which affects entire families, especially the education of healthy siblings. The familial clustering and the unknown etiology made many separate from the affected children when eating, sleeping, and having seizures because of a fear of transmission through saliva. Families struggle to provide care with minimal resources and have experienced a reduction in visitors since their children were affected by nodding syndrome. There were signs of apathy in patterns of care, and, generally, parents felt that antiepileptic medicine had brought only slight improvement in their child's condition because many had begun treatment when developmental milestones had already been lost.

CONCLUSIONS

A consistent supply of antiepileptic medication is likely to reduce the stigma and fear of transmission, as the affected children's acceptance among others was greatly compromised whenever they had seizures. The loss and suffering involved with nodding syndrome are seen as a continuation of the confinement and trauma once caused by war, and a good regimen of medication is not the whole answer.

Physical growth, puberty and hormones in adolescents with Nodding Syndrome; a pilot study

Background

Nodding syndrome is an epidemic symptomatic generalized epilepsy syndrome of unknown cause in Eastern Africa. Some patients have extreme short stature. We hypothesized that growth failure in nodding syndrome is associated with specific endocrine dysfunctions. In this pilot study, we examined the relationship between serum hormone levels and stature, bone age and sexual development.

Results

We recruited ten consecutive children, 13 years or older, with World Health Organization defined nodding syndrome and assessed physical growth, bone age, development of secondary sexual characteristics and serum hormone levels. Two children with incomplete results were excluded. Of the eight remaining, two had severe stunting (height for age Z [HAZ] score < -3) and three had moderate stunting (HAZ score between-3 and -2). The bone age was delayed by a median 3(range 0-4) years. Serum growth hormone levels were normal in all eight but the two patients with severe stunting and one with moderate stunting had low levels of Somatomedin C (Insulin like Growth Factor [IGF1]) and/or IGF binding protein 3 (IGFBP3), mediators of growth hormone function. A linear relationship was observed between serum IGF1 level and HAZ score. With the exception of one child, all were either pre-pubertal or in early puberty (Tanner stages 1 and 2) and in the seven, levels of the gonadotrophins (luteinising and follicle stimulating hormone) and the sex hormones (testosterone/oestrogen) were all within pre-pubertal ranges or ranges of early puberty. Thyroid function, prolactin, adrenal, and parathyroid hormone levels were all normal.

Conclusions

Patients with nodding syndrome may have dysfunctions in the pituitary growth hormone and pituitary gonadal axes that manifest as stunted growth, delayed bone age and puberty. Studies are required to determine if such endocrine dysfunction is a primary manifestation of the disease or a secondary consequence of chronic ill health and malnutrition and if so, whether targeted interventions can improve outcome.

Patients with nodding syndrome in Uganda improve with symptomatic treatment: a cross-sectional study

OBJECTIVES

Nodding syndrome (NS) is a poorly understood neurological disorder affecting thousands of children in Africa. In March 2012, we introduced a treatment intervention that aimed to provide symptomatic relief. This intervention included sodium valproate for seizures, management of behaviour and emotional difficulties, nutritional therapy and physical rehabilitation. We assessed the clinical and functional outcomes of this intervention after 12 months of implementation.

DESIGN

This was a cross-sectional study of a cohort of patients with NS receiving the specified intervention. We abstracted preintervention features from records and compared these with the current clinical status. We performed similar assessments on a cohort of patients with other convulsive epilepsies (OCE) and compared the outcomes of the two groups.

PARTICIPANTS

Participants were patients with WHO-defined NS and patients with OCE attending the same centres.

OUTCOME MEASURES

The primary outcome was the proportion of patients with seizure freedom (≥1 month without seizures). Secondary outcome measures included a reduction in seizure frequency, resolution of behaviour and emotional difficulties, and independence in basic self-care.

RESULTS

Patients with NS had had a longer duration of symptoms (median 5 (IQR 3, 6) years) compared with those with OCE (4 (IQR 2, 6) years), p<0.001. The intervention resulted in marked improvements in both groups; compared to the preintervention state, 121/484 (25%) patients with NS achieved seizure freedom and there was a >70% reduction in seizure frequency; behaviour and emotional difficulties resolved in 194/327 (59%) patients; 193/484 (40%) patients had enrolled in school including 17.7% who had earlier withdrawn due to severe seizures, and over 80% had achieved independence in basic self-care. These improvements were, however, less than that in patients with OCE of whom 243/476 (51.1%) patients were seizure free and in whom the seizure frequency had reduced by 86%.

CONCLUSIONS

Ugandan children with NS show substantial clinical and functional improvements with symptomatic treatments suggesting that NS is probably a reversible encephalopathy.

'You sit in fear': understanding perceptions of nodding syndrome in post-conflict northern Uganda

Background

Nodding syndrome, a disabling epidemic epileptic encephalopathy, has affected an estimated 1,834 children in northern Uganda, with reports of as many as 3,000. Etiology is unknown and children are being treated symptomatically but inconsistently with anti-epileptic drugs.

Design

This qualitative study comprised 10 semi-structured interviews with caregivers of affected children and five focus group discussions with 23 participants; relatives, teachers, and religious leaders. Data collection and participant observation were carried out from July to September 2012 in Kitgum and Pader districts. The material was coded through inductive thematic analysis.

Results

Nodding syndrome has brought signs of discrimination in school admission procedures, founded in a fear of transmission. The suffering and loss caused by nodding syndrome is collective, and participants felt that nodding syndrome was viewed as a threat to the Acholi only, and that interventions had therefore been delayed. Multiple theories of causation exist, most commonly that the disease is caused by chemicals from bombs or that food aid distributed in IDP camps had expired or been poisoned.

A feeling of uncertainty was present in all focus group discussions, fueled by the fact that results of investigations were not being shared with the communities. It was especially agonizing that CDC results had been given to the Ugandan government in 2010 but not to the public. The definitive fear is that the disease will be the end of the Acholi.

Conclusions

This study provided insight into the perceptions of communities affected by an unknown emerging disease. Families of affected children are grieving not only their child's illness; it is a loss of social value and of lineage. The loss and suffering involved with nodding syndrome should be seen in the context of the wider suffering of a society disrupted by violent conflict. The memory of war is omnipresent and is also how nodding syndrome is understood.

Epidemiology, causes, and treatment of epilepsy in sub-Saharan Africa

SUMMARY

Epilepsy is a common neurological disease in tropical countries, particularly in sub-Saharan Africa. Previous work on epilepsy in sub-Saharan Africa has shown that many cases are severe, partly a result of some specific causes, that it carries a stigma, and that it is not adequately treated in many cases. Many studies on the epidemiology, aetiology, and management of epilepsy in sub-Saharan Africa have been reported in the past 10 years. The prevalence estimated from door-to-door studies is almost double that in Asia, Europe, and North America. The most commonly implicated risk factors are birth trauma, CNS infections, and traumatic brain injury. About 60% of patients with epilepsy receive no antiepileptic treatment, largely for economic and social reasons. Further epidemiological studies should be a priority to improve understanding of possible risk factors and thereby the prevention of epilepsy in Africa, and action should be taken to improve access to treatment.

Nodding syndrome in Tanzania may not be associated with circulating anti-NMDA-and anti-VGKC receptor antibodies or decreased pyridoxal phosphate serum levels-a pilot study

BACKGROUND

Nodding syndrome (NS) is a seemingly progressive epilepsy disorder of unknown underlying cause. We investigated association of pyridoxal-phosphate serum levels and occurrence of anti-neuronal antibodies against N-methyl-D-aspartate (NMDA) receptor and voltage gated potassium channel (VGKC) complex in NS patients.

METHODS

Sera of a Tanzanian cohort of epilepsy and NS patients and community controls were tested for the presence of anti-NMDA-receptor and anti-VGKC complex antibodies by indirect immunofluorescence assay. Furthermore pyridoxal-phosphate levels were measured.

RESULTS

Auto-antibodies against NMDA receptor or VGKC (LG1 or Caspr2) complex were not detected in sera of patients suffering from NS (n=6), NS plus other seizure types (n=16), primary generalized epilepsy (n=1) and community controls without epilepsy (n=7). Median Pyridoxal-phosphate levels in patients with NS compared to patients with primary generalized seizures and community controls were not significantly different. However, these median pyridoxal-phosphate levels are significantly lower compared to the range considered normal in Europeans.

CONCLUSIONS

In this pilot study NS was not associated with serum anti-NMDA receptor or anti-VGKC complex antibodies and no association to pyridoxal-phosphate serum levels was found.

The EEG of tropical encephalopathies

In addition to encountering most of the conditions treated by clinicians in the West, clinicians in the tropics are faced with unique tropical encephalopathies. These are largely but not entirely infectious in nature. Despite the relatively low cost of EEG technology, it remains unavailable in many low-income tropical settings even at the tertiary care level. Where available, the EEG recordings and interpretation are often of unacceptable quality. Nonetheless, there are existing data on the EEG patterns seen in malaria and a number of tropical viral, bacterial, and parasitic infestations.

Nodding syndrome

An epidemic illness characterized by head nodding associated with onchocerciasis has been described in eastern Africa since the early 1960s; we summarize published reports and recent studies. Onset of nodding occurs in previously healthy 5-15-year-old children and is often triggered by eating or cold temperatures and accompanied by cognitive impairment. Its incidence has increased in Uganda and South Sudan over the past 10 years. Four case-control studies identified modest and inconsistent associations. There were nonspecific lesions seen by magnetic resonance imaging, no cerebrospinal fluid inflammation, and markedly abnormal electroencephalography results. Nodding episodes are atonic seizures. Testing has failed to demonstrate associations with trypanosomiasis, cysticercosis, loiasis, lymphatic filariasis, cerebral malaria, measles, prion disease, or novel pathogens; or deficiencies of folate, cobalamin, pyridoxine, retinol, or zinc; or toxicity from mercury, copper, or homocysteine. There is a consistent enigmatic association with onchocerciasis detected by skin snip or serologic analysis. Nodding syndrome is an unexplained epidemic epilepsy.

The challenges of managing children with epilepsy in Africa

Children with epilepsy who reside in the African continent are faced with some of the greatest challenges of receiving adequate care. The burden of disease is exacerbated by the high incidence of acquired causes and the large treatment gap. Skilled teams to identify and care for children with epilepsy are lacking. Many patients are managed through psychiatric services, thus potentially compounding the stigma associated with the condition. Little data exist to assess the true proportion of comorbidities suffered by children with epilepsy, the assumption is that this is high, further aggravated by delayed interventions and adverse responses to some of the more commonly used antiepileptic drugs.

Nodding syndrome or disease? On the conceptualization of an illness-in-the-making

OBJECTIVE

To explore processes of conceptualizing nodding syndrome (NS), an unknown illness which has been reported to affect thousands of children in post-conflict northern Uganda, in South Sudan and in Tanzania.

DESIGN

This qualitative study comprised 40 in-depth interviews with affected families, health workers and politicians during five months of fieldwork in northern Uganda and a review of available reports, newspapers and academic literature on NS. In addition, observations have been made at treatment centers and during outreaches and meetings. Focus is put on how meanings of key terms related to NS are produced and negotiated. Attention is being paid to the circulation of different discourses and explanatory models.

RESULTS

Discourses and explanatory models play an active role in the conceptualization of illness, as much by medical personnel as by affected families and the media. The prominent use of biomedical terms in the academic discourse on NS is striking; links are suggested with onchocerciasis and epilepsy. In contrast, the local discourse associates NS with social issues. The illness experiences are connected to the trauma of past conflict, to poverty and to (region-bound) frustration over neglect. The cultural significance of physical symptoms raises the question of the impact of culture on health.

CONCLUSION

By only looking at the biomedical significance of this new syndrome, we will miss important aspects of how this illness is being experienced and understood. In our future dealings with NS, we will have to consider and re-conceive the relation between culture and neurobiology.

A longitudinal study on nodding syndrome--a new African epilepsy disorder

OBJECTIVES

Nodding syndrome (NS), a new epilepsy disorder of sub-Saharan Africa, has only recently been classified. In a study conducted in southern Tanzania in 2005, 62 patients with NS were analyzed in great detail. The present study, a follow-up investigation, was conducted to evaluate the progression of NS over time and to obtain serial electroencephalography (EEG) data.

METHODS

Of the 62 NS patients, 53 (85.5%), the majority of whom were currently on some form of antiepileptic treatment, could be reevaluated in 2009 with a standardized questionnaire. A subset of these patients (25/53) underwent EEG investigation.

RESULTS

In patients with "head nodding (HN) only" in 2005, 10 (43.5%) of 23 remained with the same diagnosis, whereas 5 (21.7%) of 23 had developed "HN plus" (i.e., HN and generalized tonic-clonic seizures). Six patients (26.1%) had seizures other than HN only, and two patients (8.7%) had fully recovered. In the "HN plus" group of 2005, 9 (30.0%) of 30 patients remained "HN plus," and 15 patients (50.0%) had seizures other than HN only. Four patients (13.3%) reverted to "HN only," and two patients (6.7%) stopped all seizures. In 11 (44.0%) of 25 patients, electroencephalography (EEG) showed generalized slowing. Six (54.6%) of these 11 abnormal EEG studies further showed generalized epileptiform discharges: (1) ictal electroencephalographic pattern with generalized 2.5 Hz spike and waves in two patients and (2) interictal bursts of 1.5-2 Hz spike and waves in four patients.

SIGNIFICANCE

This follow-up study confirms that HN represents an epilepsy disorder, possibly of the atypical absence type with dynamic development over time.

Stereotypes on Nodding syndrome: responses of health workers in the affected region of northern Uganda

BACKGROUND

Nodding Syndrome is a debilitating disorder of yet unknown etiology that has affected children and adolescents aged 3 - 18 years in parts of sub Saharan African countries including Uganda, South Sudan, Tanzania and Liberia.

OBJECTIVE

To identify stereotypes and negative attitudes held by primary care health workers about nodding syndrome.

METHOD

Of one hundred health workers invited by the Uganda Ministry of Health for training on nodding syndrome from the three most affected districts of Pader, Lamwo and Kitgum forty were interviewed using a predesigned tool. Content and thematic analysis was applied.

RESULTS

There were 22 females. The median age was 33 years (range 23-54 years). The participants included Psychiatric Clinical Officers, Medical Clinical Officers, Laboratory Technicians, Midwives, Registered and Enrolled Nurses. Overall, four broad categories of negative stereotypes were identified; Nodding syndrome is 1) an incurable disease, 2) is associated with evil spirits and curses, 3) is disabling, making the patient a burden to society and 4) is a fatal illness.

CONCLUSION

Primary health care workers who lead the care of patients with nodding syndrome have several negative stereotypes that may potentially impact negatively on the quality of care they provide.

Neurological manifestations of filarial infections

Filarial infections cause a huge public health burden wherever they are endemic. These filaria may locate anywhere in the human body. Their manifestations and pathogenic mechanisms, except the most common ones, are rarely investigated systematically. Their neurological manifestations, however, are being increasingly recognized particularly with onchocerciasis or Loa loa infections, Wuchereria bancrofti, or Mansonella perstans. The risk of developing these manifestations may also increase in cases that harbor multiple filariasis or coinfections, for instance as with Plasmodium. The microfilaria of Onchocerca and Loa loa are seen in cerebrospinal fluid. The pathogenesis of neurological manifestations of these infections is complex; however, pathogenic reactions may be caused by mechanical disruption, e.g., degeneration often followed by granulomas, causing fibrosis or mass effects on other tissues, vascular lesions, e.g., vascular block of cerebral vessels, or disordered inflammatory responses resulting in meningitis, encephalitis or localized inflammatory responses. The chances of having neurological manifestations may also depend upon the frequency and"heaviness"of infection over a lifetime. Hence, this type of infection should no longer be considered a disease of the commonly affected areas but one that may produce systemic effects or other manifestations, and these should be considered in populations where they are endemic.

An Epidemiologic Investigation of Potential Risk Factors for Nodding Syndrome in Kitgum District, Uganda

INTRODUCTION

Nodding Syndrome (NS), an unexplained illness characterized by spells of head bobbing, has been reported in Sudan and Tanzania, perhaps as early as 1962. Hypothesized causes include sorghum consumption, measles, and onchocerciasis infection. In 2009, a couple thousand cases were reportedly in Northern Uganda.

METHODS

In December 2009, we identified cases in Kitgum District. The case definition included persons who were previously developmentally normal who had nodding. Cases, further defined as 5- to 15-years-old with an additional neurological deficit, were matched to village controls to assess risk factors and test biological specimens. Logistic regression models were used to evaluate associations.

RESULTS

Surveillance identified 224 cases; most (95%) were 5-15-years-old (range = 2-27). Cases were reported in Uganda since 1997. The overall prevalence was 12 cases per 1,000 (range by parish = 0·6-46). The case-control investigation (n = 49 case/village control pairs) showed no association between NS and previously reported measles; sorghum was consumed by most subjects. Positive onchocerciasis serology [age-adjusted odds ratio (AOR1) = 14·4 (2·7, 78·3)], exposure to munitions [AOR1 = 13·9 (1·4, 135·3)], and consumption of crushed roots [AOR1 = 5·4 (1·3, 22·1)] were more likely in cases. Vitamin B6 deficiency was present in the majority of cases (84%) and controls (75%).

CONCLUSION

NS appears to be increasing in Uganda since 2000 with 2009 parish prevalence as high as 46 cases per 1,000 5- to 15-year old children. Our results found no supporting evidence for many proposed NS risk factors, revealed association with onchocerciasis, which for the first time was examined with serologic testing, and raised nutritional deficiencies and toxic exposures as possible etiologies.

MRI findings in people with epilepsy and nodding syndrome in an area endemic for onchocerciasis: an observational study

BACKGROUND

Onchocerciasis has been implicated in the pathogenesis of epilepsy. The debate on a potential causal relationship between Onchocerca volvulus and epilepsy has taken a new direction in the light of the most recent epidemic of nodding syndrome.

OBJECTIVE

To document MRI changes in people with different types of epilepsy and investigate whether there is an association with O. volvulus infection.

METHODS

In a prospective study in southern Tanzania, an area endemic for O. volvulus with a high prevalence of epilepsy and nodding syndrome, we performed MRI on 32 people with epilepsy, 12 of which suffered from nodding syndrome. Polymerase chain reaction (PCR) of O. volvulus was performed in skin and CSF.

RESULTS

The most frequent abnormalities seen on MRI was atrophy (twelve patients (37.5%)) followed by intraparenchymal pathologies such as changes in the hippocampus (nine patients (28.1%)), gliotic lesions (six patients (18.8%)) and subcortical signal abnormalities (three patients (9.4%)). There was an overall trend towards an association of intraparenchymal cerebral pathologies and infection with O. volvulus based on skin PCR (Fisher's Exact Test p=0.067) which was most pronounced in children and adolescents with nodding syndrome compared to those with other types of epilepsy (Fisher's Exact Test, p=0.083). Contrary to skin PCR results, PCR of CSF was negative in all patients.

CONCLUSION

The observed trend towards an association of intraparenchymal cerebral pathological results on MRI and a positive skin PCR for O. volvulus despite negative PCR of CSF is intriguing and deserves further attention.

Nodding syndrome: origins and natural history of a longstanding epileptic disorder in sub-Saharan Africa

BACKGROUND

Repetitive involuntary head nodding was first reported in the 1960s in the Wapogoro tribe of Tanzania.

OBJECTIVES

We describe the natural history of head nodding in the Wapogoro tribe, with special reference to the earliest reported dates of onset.

METHODS

We analyzed clinical data from 150 historical patients seen between 1960 and 1971.

RESULTS

Head nodding with or without grand mal convulsions was present in 33/150 (∼20%) cases, was mostly familial and equally distributed by gender. Age at onset of head nodding ranged from 2-22 years (mean: ∼10 years) in the period 1934-1962. Head nodding preceded onset of grand mal convulsions by up to 12 months, and motor and psychomotor deficits indicative of brain damage developed with time. Fourteen of the 33 cases died at 13-39 years of age (mean: ∼20 years) while nineteen aged 16-28 years (mean: ∼16 years) were still alive.

CONCLUSION

Historical accounts of head nodding (amesinzia kichwa, Swahili) among the Wapogoro tribe fit the August 2012 World Health Organization (WHO) case definition of probable Nodding Syndrome. Reported to have existed in this population for at least 80 years, Nodding Syndrome is a progressive seizure disorder that leads to generalized convulsions (kifafa), brain damage and death.

Proposed guidelines for the management of nodding syndrome

Nodding Syndrome is a poorly understood neurologic disorder of unknown aetiology that affects children and adolescents in Africa. Recent studies have suggested that the head nods are due to atonic seizures and Nodding Syndrome may be classified as probably symptomatic generalised epilepsy. As part of the Ugandan Ministry of Health clinical management response, a multidisciplinary team developed a manual to guide the training of health workers with knowledge and skills to manage the patients. In the absence of a known cause, it was decided to offer symptomatic care. The objective is to relieve symptoms, offer primary and secondary prevention for disability and rehabilitation to improve function. Initial management focuses on the most urgent needs of the patient and the immediate family until 'stability' is achieved. The most important needs were considered as seizure control, management of behavioural and psychiatric difficulties, nursing care, nutritional and subsequently, physical and cognitive rehabilitation. This paper summarises the processes by which the proposed guidelines were developed and provides an outline of the specific treatments currently being provided for the patients.

Neuropsychiatric perspectives on nodding syndrome in northern Uganda: a case series study and a review of the literature

BACKGROUND

Nodding Syndrome (NS), previously called Nodding Disease, is a chronic and debilitating illness affecting thousands of children aged 3-18 years in post-conflict Northern Uganda and South Sudan. Characterised by malnutrition, stunted growth, mental retardation and seizures, some researchers have designated it as epilepsy. With reports appearing in Northern Uganda in1997, NS reached epidemic proportions around 2000-2003 when people were moved into Internally Displaced People's (IDP) camps. Investigations for infections (onchocerciasis) and toxins have been inconclusive as to cause, treatment or outcome. No study has addressed the possible relationship of NS to childhood war-trauma experiences.

OBJECTIVE

To explore a possible relationship of exposure to prolonged war-trauma and the emergence of epidemic NS in Northern Uganda.

METHOD

This study was a case-series descriptive psychiatric naturalistic field observations of NS cases from homesteads in Northern Uganda and psychiatric investigations and treatment of NS cases referred to Mulago National Referral and Teaching Hospital.

RESULTS

Detailed Psychiatric clinical evaluations and field observations revealed that NS children had been exposed to severe war-related psychological and physical trauma as well as non-specific CNS insults including untreated CNS infections/infestations and malnutrition possibly causing seizures. Many children suffered post-traumatic stress disorder (PTSD) and depression.

CONCLUSION

NS could present as an association of childhood complex PTSD, (called Developmental Trauma Disorder), occurring in the chronically war-traumatised children of Northern Uganda, complicated by severe prolonged depression with its characteristic symptoms of psychomotor retardation, anxiety, anhedonia and anorexia. This, coupled with food shortages, resulted in malnutrition, wasting and stunted growth with severe avitaminoses. Many children had seizures. All this calls for multi-disciplinary treatment approaches.

Nodding syndrome in Mundri county, South Sudan: environmental, nutritional and infectious factors

BACKGROUND

Nodding Syndrome is a seizure disorder of children in Mundri County, Western Equatoria, South Sudan. The disorder is reported to be spreading in South Sudan and northern Uganda.

OBJECTIVE

To describe environmental, nutritional, infectious, and other factors that existed before and during the de novo 1991 appearance and subsequent increase in cases through 2001.

METHODS

Household surveys, informant interviews, and case-control studies conducted in Lui town and Amadi village in 2001-2002 were supplemented in 2012 by informant interviews in Lui and Juba, South Sudan.

RESULTS

Nodding Syndrome was associated with Onchocerca volvulus and Mansonella perstans infections, with food use of a variety of sorghum (serena) introduced as part of an emergency relief program, and was inversely associated with a history of measles infection. There was no evidence to suggest exposure to a manmade neurotoxic pollutant or chemical agent, other than chemically dressed seed intended for planting but used for food. Food use of cyanogenic plants was documented, and exposure to fungal contaminants could not be excluded.

CONCLUSION

Nodding Syndrome in South Sudan has an unknown etiology. Further research is recommended on the association of Nodding Syndrome with onchocerciasis/mansonelliasis and neurotoxins in plant materials used for food.

Nodding syndrome in Ugandan children--clinical features, brain imaging and complications: a case series

OBJECTIVES

Nodding syndrome is a devastating neurological disorder of uncertain aetiology affecting children in Africa. There is no diagnostic test, and risk factors and symptoms that would allow early diagnosis are poorly documented. This study aimed to describe the clinical, electrophysiological and brain imaging (MRI) features and complications of nodding syndrome in Ugandan children.

DESIGN

Case series.

PARTICIPANTS

22 children with nodding syndrome brought to Mulago National Referral Hospital for assessment.

OUTCOME MEASURES

Clinical features, physical and functional disabilities, EEG and brain MRI findings and a staging system with a progressive development of symptoms and complications.

RESULTS

The median age of symptom onset was 6 (range 4-10) years and median duration of symptoms was 8.5 (range 2-11) years. 16 of 22 families reported multiple affected children. Physical manifestations and complications included stunting, wasting, lip changes and gross physical deformities. The bone age was delayed by 2 (range 1-6) years. There was peripheral muscle wasting and progressive generalised wasting. Four children had nodding as the only seizure type; 18 in addition had myoclonic, absence and/or generalised tonic-clonic seizures developing 1-3 years after the onset of illness. Psychiatric manifestations included wandering, aggression, depression and disordered perception. Cognitive assessment in three children demonstrated profound impairment. The EEG was abnormal in all, suggesting symptomatic generalised epilepsy in the majority. There were different degrees of cortical and cerebellar atrophy on brain MRI, but no hippocampal changes. Five stages with worsening physical, EEG and brain imaging features were identified: a prodrome, the development of head nodding and cognitive decline, other seizure types, multiple complications and severe disability.

CONCLUSIONS

Nodding syndrome is a neurological disorder that may be characterised as probably symptomatic generalised epilepsy. Clinical manifestations and complications develop in stages which might be useful in defining treatment and rehabilitation. Studies of risk factors, pathogenesis, management and outcome are urgently needed.

Case-control studies on the relationship between onchocerciasis and epilepsy: systematic review and meta-analysis

OBJECTIVE

A systematic review and meta-analysis of all available case-control studies on the relationship between onchocerciasis and epilepsy. Because age and level of onchocerciasis endemicity in the area of residence are major determinants for infection, an additional analysis was performed, restricted to studies achieving control of these confounding factors.

DATA SOURCES

Medical databases, the "African Neurology Database, Institute of Neuroepidemiology and Tropical Neurology, Limoges," reference lists of relevant articles, commercial search engines, up to May 2012.

METHODS

We searched for studies examining infection status with Onchocerca volvulus in persons with epilepsy (PWE) and without epilepsy (PWOE) providing data suitable for the calculation of pooled odds ratios (ORp) and/or standardized mean differences (SMD) using random-effects models.

RESULTS

Eleven studies providing data of qualitative skin biopsies for diagnosis of onchocerciasis were identified. Combined analysis on the total sample of 876 PWE and 4712 PWOE resulted in an ORp of 2.49 (95% confidence interval (95%CI): 1.61-3.86, p<0.001). When this analysis was restricted to those studies achieving control for age, residence and sex (367 PWE, 624 PWOE), an ORp of 1.29 (95% CI: 0.93-1.79; p = 0.139) was found. Presence of nodules for diagnosis of onchocerciasis was analyzed in four studies (225 PWE, 189 PWOE; ORp 1.74; 95%CI: 0.94-3.20; p<0.076), including two studies of the restricted analysis (106 PWE, 106 PWOE; ORp 2.81; 95%CI: 1.57-5.00; p<0.001). One study examined quantitative microfilariae counts in patients without preceding microfilaricidal treatment and demonstrated significantly higher counts in PWE than in PWOE.

INTERPRETATION

Our results strengthen the hypothesis that, in onchocerciasis foci, epilepsy and infection with O. volvulus are associated. Analysis of indicators giving information on infection intensity, namely nodule palpation and quantitative microfilaria count in untreated patients, support the hypothesis that intensity of infection with O. volvulus is involved in the etiology of epilepsy.

Clinical, neurological, and electrophysiological features of nodding syndrome in Kitgum, Uganda: an observational case series

BACKGROUND

Nodding syndrome is an unexplained illness characterised by head-bobbing spells. The clinical and epidemiological features are incompletely described, and the explanation for the nodding and the underlying cause of nodding syndrome are unknown. We aimed to describe the clinical and neurological diagnostic features of this illness.

METHODS

In December, 2009, we did a multifaceted investigation to assess epidemiological and clinical illness features in 13 parishes in Kitgum District, Uganda. We defined a case as a previously healthy child aged 5-15 years with reported nodding and at least one other neurological deficit. Children from a systematic sample of a case-control investigation were enrolled in a clinical case series which included history, physical assessment, and neurological examinations; a subset had electroencephalography (EEG), electromyography, brain MRI, CSF analysis, or a combination of these analyses. We reassessed the available children 8 months later.

FINDINGS

We enrolled 23 children (median age 12 years, range 7-15 years) in the case-series investigation, all of whom reported at least daily head nodding. 14 children had reported seizures. Seven (30%) children had gross cognitive impairment, and children with nodding did worse on cognitive tasks than did age-matched controls, with significantly lower scores on tests of short-term recall and attention, semantic fluency and fund of knowledge, and motor praxis. We obtained CSF samples from 16 children, all of which had normal glucose and protein concentrations. EEG of 12 children with nodding syndrome showed disorganised, slow background (n=10), and interictal generalised 2·5-3·0 Hz spike and slow waves (n=10). Two children had nodding episodes during EEG, which showed generalised electrodecrement and paraspinal electromyography dropout consistent with atonic seizures. MRI in four of five children showed generalised cerebral and cerebellar atrophy. Reassessment of 12 children found that six worsened in their clinical condition between the first evaluation and the follow-up evaluation interval, as indicated by more frequent head nodding or seizure episodes, and none had cessation or decrease in frequency of these episodes.

INTERPRETATION

Nodding syndrome is an epidemic epilepsy associated with encephalopathy, with head nodding caused by atonic seizures. The natural history, cause, and management of the disorder remain to be determined.

FUNDING

Division of Global Disease Detection and Emergency Response, US Centers for Disease Control and Prevention.

Nodding syndrome in northern Uganda: overview and community perspectives

The increasing prevalence of nodding syndrome in northern Uganda has generated a wide range of speculations with respect to etiology and natural history of and best possible medical treatment for this mysterious seizure disorder. Despite in-depth investigations by the United States Centers for Disease Control and Prevention and the Ministry of Health in Uganda, no clear causal factors have emerged. At the same time, northern Uganda communities are voicing concern for their lack of knowledge about nodding syndrome. The purpose of this commentary is to summarize northern Uganda community perceptions of this syndrome. These reflections demonstrate the need for larger investigations into the impact of nodding syndrome and other seizure disorders on local communities both in northern Uganda and throughout the world, in particular rural areas of resource poor countries.

Reviewing the evidence on nodding syndrome, a mysterious tropical disorder

OBJECTIVES

To review the literature on the prevalence, clinical manifestations, pathogenesis, treatment, and implications of nodding syndrome (NS).

METHODS

This is a narrative review.

RESULTS

NS is a mysterious tropical disorder that is emerging in South Sudan, southern Tanzania, and northern Uganda. Over the past decade, thousands of children have become affected, but the prevalence is unknown. NS is characterized by an occasional nodding of the head, which is considered as a form of epilepsy. After symptoms appear, the patient's health rapidly deteriorates. Seizures, stunted growth, and mental retardation may appear. In endemic areas, NS is increasingly becoming a public health problem with high morbidity and mortality, and severe social, psychological, and economic implications. However, the pathogenesis is unknown. Evidence suggests a role for Onchocerca volvulus, the parasitic filarial worm responsible for river blindness, which is highly endemic in these areas. There is no cure for NS, and treatment is symptomatic with common anticonvulsants to improve the quality of life.

CONCLUSIONS

NS seems to be a rapidly growing problem in several eastern African countries. Although it is starting to receive more and more attention in the scientific literature, little is known about NS. A better understanding of the pathogenesis may lead to prevention and treatment opportunities.

Clinical and epidemiologic characteristics of nodding syndrome in Mundri County, southern Sudan

BACKGROUND

Nodding syndrome (repetitive nodding and progressive generalized seizures) is assuming epidemic proportions in South Sudan, Tanzania and Uganda.

OBJECTIVE

To describe clinical and epidemiological features of nodding syndrome in southern Sudan based on preliminary investigations conducted in 2001 and 2002.

METHOD

Household surveys, clinical, electrophysiological (EEG) assessments, informant interviews and case-control studies were conducted in the town of Lui and the village of Amadi in southern Sudan.

RESULTS

Nodding syndrome is characterized by involuntary repetitive nodding of the head, progressing to generalized seizures; mental and physical deterioration. The EEGs were consistent with progressive epileptic encephalopathy. Prevalence of Nodding syndrome in Lui and Amadi was 2.3% and 6.7% respectively. All case control studies showed a positive association between cases and Onchocerca volvulus. A history of measles was negatively associated with being a case: 2/13 of cases and 11/19 of controls had had measles: odds ratio 0.13 (95% CI 0.02, 0.76). Environmental assessment did not reveal any naturally occurring or manmade neurotoxic factors to explain Nodding Syndrome, although fungal contamination of food could not be ruled out.

CONCLUSION

Nodding Syndrome was strongly associated with Onchocerca volvulus. There was no evidence to suggest an environmental pollutant, chemical agent, or other toxic factor.

Association between onchocerciasis and epilepsy in the Itwara hyperendemic focus, West Uganda: controlling for time and intensity of exposure

In 38 pairs of epilepsy patients and controls matched for time and intensity of exposure to transmission of onchocerciasis, the presence of microfilariae in the skin of epilepsy patients was found insignificantly elevated compared with controls (odds ratio = 1.68; 95% confidence interval [CI] = 0.60-4.57; P = 0.31). This difference was more pronounced when detection of subcutaneous nodules was used as indication of infection with Onchocerca volvulus (odds ratio = 2.77; 95% CI = 0.92-8.33; P = 0.065). These findings from a patient group of limited size suggest that intensity of infection may play a substantial role in the development of onchocerciasis-associated epilepsy. Our results are in contrast to the results of two other independent studies from the identical endemic area; one case concluded a significant positive correlation between onchocerciasis and epilepsy, and the other case concluded a clearly negative correlation. Studies with a greater sample size are needed to confirm this possible relationship.

Clinical characteristics of people with head nodding in southern Tanzania

We have previously described a seizure disorder characterized by head nodding (HN). In a prospective study in southern Tanzania, we evaluated 62 patients with HN. Here, we report the patients' clinical characteristics and those of their seizures, which indicate high seizure frequency, unsatisfactory seizure control, a high burden of cognitive impairment and disease-associated barriers to education.

The role of Onchocerca volvulus in the development of epilepsy in a rural area of Tanzania

INTRODUCTION

Several reports indicate high prevalences of both onchocerciasis and epilepsy in some regions of Africa. This raises the question of whether these diseases are associated. We therefore investigated people with epilepsy and/or onchocerciasis living in an area in Tanzania endemic for Onchocerca volvulus (O. volvulus).

METHODS

We collected clinical information, skin snips, and blood from 300 individuals, and cerebrospinal fluid (CSF) from 197. Participants were allocated to 4 groups consisting of people with epilepsy and onchocerciasis (n=135), those with either epilepsy (n=61) or onchocerciasis only (n=35), and healthy individuals (n=69). Samples were evaluated for microfilaria, IgG4 antibodies against O. volvulus, O. volvulus antibody index (CSF/serum), and CSF routine parameters. Polymerase chain reaction (PCR) was performed on skin snips and CSF.

RESULTS

No difference was found in microfilarial density between participants with and without epilepsy (P=0.498). The antibody index was raised in 2 participants. CSF PCR was negative in all samples tested.

DISCUSSION

Our results do not give evidence of a relationship between O. volvulus and epilepsy. Despite the fact that 2 participants had raised antibody index, the existence of cerebral onchocerciasis caused by migration of microfilariae into the CSF appears unlikely. However, to date unexplored reactions to the infestation with O. volvulus causing epilepsy cannot be excluded.