[Survey of investigation around cases of Rift Valley Fever at Tagant, Mauritania]. / Enquête d'investigation sur des cas de fièvre de la vallée du Rift au Tagant, Mauritanie.

BACKGROUND: Rift Valley Fever (RVF) is a zoonotic arbovirosis. Among animals, it mainly affects ruminants, causing abortions in gravid females and deaths among young animals. In humans, RVF virus infection is usually asymptomatic or characterized by a moderate fever. However, in 1-3% of cases, the disease progresses to a severe form with 50% mortality. OBJECTIVE: Search for risk factors and to propose appropriate measures to prevent the potential for extension of the epidemic, and to make recommendations for disease monitoring and control. METHODS: This investigation involved human RVF cases reported between October 12 and November 20, 2012 in the area of Tagant in Mauritania. Arbovirosis diagnosis was established by the laboratory of the National Institute of Public Health Research in Nouakchott (Mauritania) in collaboration with the Pasteur Institute of Dakar (Senegal). RESULTS: Of 212 subjects, RVF serology was positive in 26 (12%). Among those seropositive for RVF, 11 (42%) had severe hemorrhagic forms. The case fatality rate was 91%. A series of animal abortions (cattle, sheep and goats) was observed in the area where all but two subjects resided. Exposure to potential risk factors for RVF virus infection was found in all patients. CONCLUSION: Mortality is very high in the hemorrhagic forms of RVF. Disease prevention is necessary by strengthening the fight against vectors, avoiding contact and consumption of organic products from diseased animals and vaccination of animals in areas where the disease is endemic. Furthermore, it is essential to establish management procedures for patients infected with the RVF virus. An appropriately equipped referral hospital is necessary, together with strengthened epidemiological surveillance by notifying all suspected cases of hemorrhagic fevers.

Molecular diversity of the ammonia-oxidizing bacteria community in disused tin-mining ponds located within Kampar, Perak, Malaysia.

Disused tin-mining ponds make up a significant amount of water bodies in Malaysia particularly at the Kinta Valley in the state of Perak where tin-mining activities were the most extensive, and these abundantly available water sources are widely used in the field of aquaculture and agriculture. However, the natural ecology and physicochemical conditions of these ponds, many of which have been altered due to secondary post-mining activities, remains to be explored. As ammonia-oxidizing bacteria (AOB) are directly related to the nutrient cycles of aquatic environments and are useful bioindicators of environmental variations, the focus of this study was to identify AOBs associated with disused tin-mining ponds that have a history of different secondary activities in comparison to ponds which were left untouched and remained as part of the landscape. The 16S rDNA gene was used to detect AOBs in the sediment and water sampled from the three types of disused mining ponds, namely ponds without secondary activity, ponds that were used for lotus cultivation and post-aquaculture ponds. When the varying pond types were compared with the sequence and phylogenetic analysis of the AOB clone libraries, both Nitrosomonas and Nitrosospira-like AOB were detected though Nitrosospira spp. was seen to be the most ubiquitous AOB as it was present in all ponds types. However, AOBs were not detected in the sediments of idle ponds. Based on rarefaction analysis and diversity indices, the disused mining pond with lotus culture indicated the highest richness of AOBs. Canonical correspondence analysis indicated that among the physicochemical properties of the pond sites, TAN and nitrite were shown to be the main factors that influenced the community structure of AOBs in these disused tin-mining ponds.

Molecular diversity of the methanotrophic bacteria communities associated with disused tin-mining ponds in Kampar, Perak, Malaysia.

In a previous study, notable differences of several physicochemical properties, as well as the community structure of ammonia oxidizing bacteria as judged by 16S rRNA gene analysis, were observed among several disused tin-mining ponds located in the town of Kampar, Malaysia. These variations were associated with the presence of aquatic vegetation as well as past secondary activities that occurred at the ponds. Here, methane oxidizing bacteria (MOB), which are direct participants in the nutrient cycles of aquatic environments and biological indicators of environmental variations, have been characterised via analysis of pmoA functional genes in the same environments. The MOB communities associated with disused tin-mining ponds that were exposed to varying secondary activities were examined in comparison to those in ponds that were left to nature. Comparing the sequence and phylogenetic analysis of the pmoA clone libraries at the different ponds (idle, lotus-cultivated and post-aquaculture), we found pmoA genes indicating the presence of type I and type II MOB at all study sites, but type Ib sequences affiliated with the Methylococcus/Methylocaldum lineage were most ubiquitous (46.7 % of clones). Based on rarefaction analysis and diversity indices, the disused mining pond with lotus culture was observed to harbor the highest richness of MOB. However, varying secondary activity or sample type did not show a strong variation in community patterns as compared to the ammonia oxidizers in our previous study.

[Rhegmatogenous retinal detachment: Topography of breaks and agreement with lincoff's rules]. / Décollement de rétine rhegmatogène : topographie des déhiscences et conformité aux lois de Lincoff.

PURPOSE: To study the topography of retinal breaks and their agreement with Lincoff's rules. MATERIALS AND METHODS: We performed a retrospective descriptive study of patients with recent rhegmatogenous retinal detachments followed on the ophthalmology service of Abass Ndao Hospital from January 2006 through December 2016. Patients with no prior retinal treatment were included. RESULTS: Over 11 years, we reviewed 97 patients with 107 eyes with retinal detachments. The mean age of our patients was 51.7 years, range 23-79 years. There were 69 male patients, for a male:female ratio of 2.46. Refraction revealed that 38.1% of patients were myopes. Fourteen percent (14%) of patients had experienced trauma to the eye with the detachment. The right eye was involved in 54.6% of patients. The onset was insidious in 54.6% of cases and sudden in 23.7% of cases. All patients had decreased visual acuity, associated with a scotoma in 26.8% of cases. Visual acuity was decreased to light perception through 7/10. In 64.9% of cases, Lincoff's rules were observed. DISCUSSION: Lincoff's rules are still relevant for localization of the breaks in retinal detachments. CONCLUSION: Diagnosis of a retinal detachment is an essential step, since it determines the treatment. Lincoff's rules still have a role in finding the retinal break in retinal detachments.

Influence of physicochemical parameters on the spatial distribution of snail species that are intermediate hosts of human schistosomes in the Senegal River Delta.

The objective of this work was to identify possible correlations between physicochemical parameters (water temperature, water flow velocity, electrical conductivity, dissolved oxygen, salinity, pH, nitrates, and phosphates) and the spatial distribution in the Senegal River delta of snail species that are intermediate hosts of human schistosomes. Eight water points (ME1 to ME4, NE1 and NE2, TA1 and TA2) were selected in the villages of Menguègne Boye, Ndellé Boye, and Thilla for biweekly monitoring of these snails and the physicochemical parameters of the water. The results show that the spatial distribution of the snail populations is related to pH, dissolved oxygen (mg/l), conductivity, temperature (̊C), and water flow velocity (m/s).

Kinetics of maternally-derived serogroup A, C, Y and W-specific meningococcal immunoglobulin G in Malian women and infants.

A prospective, randomised, controlled observer-blind trial measuring the efficacy and immunogenicity of trivalent influenza vaccine (TIV) and the immunogenicity of quadrivalent meningococcal conjugate vaccine (MCV) in pregnant women and their infants up to 6 months of age was conducted in Mali. Here we reported the immunogenicity of MCV, which was used as a comparator vaccine to TIV, in this population. Third-trimester pregnant Malian women were randomized to receive TIV or MCV. Blood samples were collected from women prior to vaccination, 28 days post-vaccination, at delivery and 3 and 6 months post-delivery and from infants at birth and 3 and 6 months of age. Meningococcal-specific serogroup (Men) A, C, Y and W-specific antibodies were measured by enzyme linked immunosorbent assay in a randomly selected subset of 50 mother-infant pairs where the mother had received MCV. At birth, 94.0% (47/50) of infants had MenA specific IgG levels ≥ 2 µg/mL decreasing to 72.9% and 30.4% at 3 and 6 months of age. For MenC, 81.3% (39/48) of infants had MenC specific IgG levels ≥ 2 µg/mL at birth decreasing to 29.4% and 17.8% at 3 and 6 months of age. For MenY, 89.6% (43/48) of infants had MenY specific IgG levels ≥ 2 µg/mL at birth decreasing to 64.6% and 62.5% at 3 and 6 months of age. For MenW, 89.6% (43/48) of infants had MenW specific IgG levels ≥ 2 µg/ml at birth decreasing to 62.5% and 41.7% at 3 and 6 months of age. Maternal immunization with MCV conveyed protective levels of IgG at birth through to 3 months of age in the majority of infants.

[Giant retinal tears: Senegalese experience]. / Aspect thérapeutique des déchirures géantes de la rétine : expérience sénégalaise.

PURPOSE: To appreciate the epidemiological characteristics and to show the therapeutic aspects of the giant retinal tears. PATIENTS AND METHODS: We conducted a retrospective study from January 2014 to June 2017 on subjects with giant retinal tears. Patients with media opacities limiting examination were excluded. RESULTS: We identified 17 cases of giant retinal tears. The frequency of detachments related to a giant retinal tear was 17% compared to all retinal tears. The mean age was 50.75 years with a sex ratio (M/F) of 6.5. We found three cases of high myopia, one case of hyperopia and four trauma cases. All patients had a decrease in visual acuity. The average time to consultation was four weeks. The mean intraocular pressure was 8mmHg. The tear was found in the left eye in eight cases and in the right eye in five cases; two cases were bilateral. We performed intraocular surgery in five eyes and laser in four eyes. We achieved anatomical reattachment and functional improvement in all operated patients. COMMENTS AND CONCLUSION: The prognosis of a giant retinal tear remains guarded, especially if patients are seen and treated late. Laser photocoagulation of giant tears remains effective, especially in cases of early diagnosis.

[Evaluation of mean macular thickness by optical coherence tomography (SD OCT) in black Senegalese subjects]. / Évaluation de l'épaisseur maculaire moyenne par la tomographie en cohérence optique (SD OCT) chez le sujet mélanoderme sénégalais.

INTRODUCTION: Our goal was to evaluate the normal macular thickness in Blacks by OCT and to determine socio-demographic and clinical parameters which may influence it. MATERIALS AND METHODS: This was a multicenter, prospective, descriptive study over 6 months. It included Black adults followed in the ophthalmology departments of Abass Ndao and Aristide-Le-Dantec hospitals in Dakar. Included subjects had corrected visual acuity of 10/10 (0 logMAR) and P2 (+0.1 logMAR), clear ocular media, and no retinal abnormalities. We used the Topcon 3D 2000 OCT to measure the central thicknesses of the cornea (CT) and of the macula (MT), and cup to disc ratio (C/D) in each eye. Socio-demographic, clinical and tomographic data were collected on a survey form and correlated to the MT. The analysis was carried out by the Epi info 7 software. We used the Chi2 comparison test with a P value˂0.05. RESULTS: One hundred and nine patients were included. The mean age was 27.39 years with a male/female ratio of 0.65. The subjects were emmetropic in 54.13% of cases. The mean CT was 519.97µm, the mean C/D was 0.23, and the mean MT was 264.35µm. The P-value (P) was greater than or equal to 0.1 for all the factors studied. CONCLUSION: MT in our study was lower than that of Whites, and the various parameters studied did not demonstrate a statistically significant influence on MT.

Strengthening immunization in a West African country: Mali.

UNLABELLED: OBJECTIVES AND CONTEXT: This paper describes the preliminary outcomes of a collaborative capacity-building initiative performed in Mali to strengthen the immunization program. METHODS: We conducted baseline assessments, training and post-training assessments in four programmatic areas: vaccine management, immunization safety, surveillance, and vaccine coverage, using adapted World Health Organization (WHO) tools. Impact assessment was done by evaluation of trainee performance, programmatic impact and sustainability. RESULTS: Qualitative and quantitative improvement of trainee performance was seen after the training interventions: some knowledge improvement, greater compliance with vaccine management practices and improved vaccine coverage. Deficiencies in information transfer to the periphery were identified. CONCLUSIONS: The program involves shared responsibility for planning, implementation and financing with national stakeholders while emphasizing the training of leaders and managers to ensure sustainability. Although short-term gains were measured, our initial assessments indicate that sustained impact will require improvements in staffing, financing and guidelines to ensure delivery of information and skills to the periphery.

[Patients' quality of life after cataract surgery]. / Qualité de vie des patients après chirurgie de la cataracte.

INTRODUCTION: Our goal is to assess the Quality of Life (QL) of our patients after cataract surgery. MATERIALS AND METHODS: We performed a multicenter prospective study from July 2012 to December 2013 including patients undergoing cataract surgery, aged 18 and older. A survey sheet with sociodemographic data, clinical data and QL survey (VF-14) was given to each patient after surgery at day 7 (D7), one month (M1) and two months (M2) postoperatively. The final score was obtained by the following formula: QL=V (%)=(F __/__ C)×25. The data analysis was performed using SPSS software. RESULTS: A total of 100 patients were included, 56 men, and 61 years was the mean age. The mean QL score was 29.86% at D7, 73.97% at M1 and 81.21% at M2. Subjects between 18 and 30 years of age had a score of 90.15% vs. 82.52% at M2 for older patients. After optical correction, the quality of life scores increased from 83.22% at D7 to 93.18% at M2. Patients who did not have functional signs had a QL score of 83.94%. Anxious patients had a QL score of 44% at D7, 61.23% at M1 and 52.67% at M2. CONCLUSION: Good surgical outcomes require, in addition to clinical success, good quality of life. Several factors may influence this quality of life.

[Rare causes of childhood leukocoria]. / Les causes rares de leucocorie chez l'enfant.

PURPOSE: The purpose was to record the causes of leukocoria among children under 10years of age and to determine the proportion of rare causes of leukocoria. PATIENTS AND METHODS: This retrospective study was conducted over a period of ten years, from January 1, 2004 to December 31, 2013, in patients under 10years of age who were referred for leukocoria. RESULTS: Leukocoria represented one of the ten reasons for consultation among children under 10years of age. The mean age of our patients was 42.5months. In 76 % of cases, the leukocoria patients were children under 6years of age. Male patients were affected more commonly, with a sex-ratio of 1.5. Patients coming from Dakar and its suburbs represented two thirds of the total. Bilateral involvement represented 53.7 % of the total. Cataracts were responsible for 74.3 % of cases, retinoblastoma 20.58 %, retinal detachment 0.96 %, retinopathy of prematurity 0.96 %, pupillary membrane persistence 0.96 %, persistent hyperplastic primary vitreous 0.64 %, endophthalmitis 0.64 %, optic nerve coloboma 0.32 %, iris heterochromia 0.32 % and ametropia 0.32 %. DISCUSSION: The total percentage of rare causes was 5.12 % in our study, including one case of hyperopia. These etiologies, although rare, do exist. CONCLUSION: Rare causes of leukocoria require special attention. The discovery of leukocoria necessitates rigorous etiological work-up. Ametropia must be a diagnosis of exclusion.

[Senegalese experience with acute viral conjunctivitis]. / Expérience sénégalaise des conjonctivites virales aiguës.

PURPOSE: To study the epidemiological and clinical aspects of acute enteroviral and adenoviral conjunctivitis. PATIENTS AND METHODS: A prospective study was conducted between January 1st and October 31st, 2015, jointly between two Ophthalmology services and a virology laboratory, which identified 51 patients. Were included all patients who presented a painful red eye without loss of visual acuity associated with secretions,evolving for less than 4weeks RESULTS: The mean age was 32 years, and the sex ratio 1:1. Over half of our patients (61%) came from populous districts. A history of the virus "going around" was reported by 30 patients (59% of cases). Virological testing was positive in 35 patients (68.7% of cases). Over 90% of samples collected during the first week of clinical signs were positive. CONCLUSION: Viral conjunctivitis is a contagious condition, the spread of which is favored by promiscuity. Adenovirus and enterovirus are the main causative agents. They are present on an endemic scale in Senegal; thus, the need for better epidemiological surveillance in order to limit spread.

[Ebola in Guinea: experience of stigma among health professional survivors]. / Ebola en Guinée : formes de la stigmatisation des acteurs de santé survivants.

This article aims to describe the various forms of stigma faced by Ebola health professional survivors. A study based on in-depth interviews with 20 survivors was conducted in Conakry as part of PostEboGui multidisciplinary cohort research Program (Life after Ebola) in July-August 2015. Participants were health professionals, male and female, mostly with precarious positions in the health system. The results show that stigmatization is mainly expressed through avoidance, rejection, or being refused to be reinstated in the position at work and non-acceptance of the disease by third parties. This stigmatization appears to be rooted in fear of contagion and in diverging conceptions of the disease aetiology that may engender conflict. Being health workers did not protect them against stigma and some of them faced rejection in their own health care facility. This stigmatization was not based on moral grounds, contrary to the one experienced by people living with HIV, and attitudes of solidarity were encountered in family and confessional networks. Responders found support within an association of survivors (Association des personnes guéries et affectées d'Ebola en Guinée, APEGUAEG) that was created in early 2015. Stigmatization was temporary and disappeared for most responders owing to strategies implemented by survivors and because the fear of contagion had vanished: interviews were conducted when the notion of persistence of Ebola virus in the semen was not spread in the population. This research study shows that stigma is perpetuated among health agents, towards workers who were exposed by their professional role. This observation should be considered for specific measures towards behavioural change. Finally, the very notion of "stigmatization", widely used by public health institutions, is challenged by the diversity of individual experiences that are particular to Ebola virus disease regarding their expression and evolution. Studies on stigma related to Ebola should be held in other populations and contexts for comparison.

Virology. Mutation rate and genotype variation of Ebola virus from Mali case sequences.

The occurrence of Ebola virus (EBOV) in West Africa during 2013-2015 is unprecedented. Early reports suggested that in this outbreak EBOV is mutating twice as fast as previously observed, which indicates the potential for changes in transmissibility and virulence and could render current molecular diagnostics and countermeasures ineffective. We have determined additional full-length sequences from two clusters of imported EBOV infections into Mali, and we show that the nucleotide substitution rate (9.6 × 10(-4) substitutions per site per year) is consistent with rates observed in Central African outbreaks. In addition, overall variation among all genotypes observed remains low. Thus, our data indicate that EBOV is not undergoing rapid evolution in humans during the current outbreak. This finding has important implications for outbreak response and public health decisions and should alleviate several previously raised concerns.

Association of NRAMP1 polymorphism with leprosy type but not susceptibility to leprosy per se in west Africans.

Twin and family studies indicate that host genetic factors influence susceptibility to leprosy and, possibly, leprosy type. Murine studies have suggested a role for the natural resistance-associated macrophage protein 1 (Nramp1) gene, which can influence cellular immune responses to intracellular pathogens. We evaluated a variation in the human homolog, NRAMP1, recently associated with tuberculosis susceptibility in West Africa. A total of 273 patients with leprosy and 201 controls from Mali were genotyped for NRAMP1 polymorphisms previously associated with tuberculosis. No association was found with leprosy per se (P = 0.83), but the NRAMP1 3'-untranslated region 4-bp insertion/deletion polymorphism was associated with leprosy type (P = 0.007). Heterozygotes were more frequent among multibacillary than paucibacillary leprosy cases. Thus, variation in or near the NRAMP1 gene may exert an influence on the clinical presentation of leprosy, possibly by influencing cellular immune response type.

Efficacy and side effects of praziquantel in an epidemic focus of Schistosoma mansoni.

Schistosoma mansoni was first reported in the area of Richard Toll (Senegal) in 1988 and spread rapidly in the community, after a series of human-engineered ecologic changes. A random population sample (n = 422) from Ndombo, a village near Richard-Toll, was studied in 1991 by stool examination (four Kato slides from two stool samples) and antigen detection in urine and blood. Stool-positive individuals were treated with 40 mg/kg of praziquantel. A house-to-house interview regarding side effects was conducted 24 hr after treatment. Two hundred ninety-eight subjects were re-examined 10 days (antigen detection) and 12 weeks (egg counts, antigen detection) after treatment. Before treatment, positive egg counts were found in 91% of the subjects, with 41% excreting more than 1,000 eggs per gram (epg) of feces. Treatment of 352 individuals caused serious but transient side effects (colic, vomiting, urticaria, and edema), the frequency of which increased with increasing egg counts. The parasitologic cure rate 12 weeks after treatment was only 18%, the frequency of egg counts with more than 1,000 epg decreased to 5%, and the mean egg count of those remaining positive was reduced by 86%. Antigen detection in serum 10 days and 12 weeks after treatment remained positive in 90% of the subjects, although titers decreased sharply. The low cure rates may be due to intense transmission and/or undeveloped immune responses in this recently exposed population. However, reduced drug susceptibility of the parasite strain has now been confirmed in one local isolate.

Organometric investigations of the spleen and liver by ultrasound in Schistosoma mansoni endemic and nonendemic villages in Senegal.

With the intention of ultrasonographically assessing hepatosplenic morbidity in Schistosoma mansoni infection and of validating the grading system applied (Cairo classification), 191 subjects in a schistosomiasis endemic village and 247 controls from a nonendemic village in northern Senegal underwent sonographic examination of the liver and spleen. Measurements of the diameters of the peripheral periportal vein branches, the main portal vein stem, liver size (left lobe and right lobe), and spleen length in the endemic village were compared with those in the nonendemic village to evaluate the much discussed influence of S. mansoni infection on those variables. To subtract this presumed influence from reference values for the named variables, they are given as measured in the nonendemic village, stratified by body weight, enabling future investigators on schistosomiasis-induced morbidity to refer to these reference values. The 95th percentile regarding peripheral periportal vein branch diameter in the control groups was exceeded in 24% of the subjects in the endemic group. It was exceeded by 6% for the main portal vein stem diameter, 13% for the left liver lobe, 12% for the right liver lobe, and 14% for the spleen length. According to the Cairo classification, 97% of the endemic population and 81% of the controls had periportal thickening of the liver, mostly grade I. We conclude that 1) hepatic morbidity in the S. mansoni endemic area was low, despite strikingly high intensities of infection; 2) the Cairo classification in its present form overestimates periportal thickening, especially in the case of mild morbidity; and 3) body height-dependent reference values, obtained from endemic controls, must be applied for organometric parameters.

The contribution of host-related factors to low cure rates of praziquantel for the treatment of Schistosoma mansoni in Senegal.

Surprisingly low cure rates were repeatedly observed after treatment with a standard dosage of praziquantel in a recently established Schistosoma mansoni focus in northern Senegal. In 4 discrete cohorts from the same population, cure rates were 18-36% and egg count reduction rates were 77-88%. Data and material of 920 compliant subjects from all 4 cohorts were further analyzed to identify possible host-related factors associated with low cure rates. The lowest cure rates were found in the highest egg count groups. However, in low and moderate egg count groups, drug efficacy was also below normal values. Cure rates were similar in males and females, showed no seasonal variation, and were independent of previous praziquantel treatment. They were significantly higher in adults than in children, also after allowing for intensity of infection. Individual water contact behavior and specific humoral immune responses were examined in 2 extreme subgroups, either without significant egg count reduction or showing complete parasitologic cure. There was no significant difference in frequency and duration of water contact between those individuals with complete cure and those that showed little effect of praziquantel treatment. Levels of IgG, IgG1, IgG3, IgG4, IgM, and IgE against adult worm antigen were not different between the 2 subgroups. Thus, the abnormally frequent failure of treatment observed in this focus could not be associated with any host-related factor, other than age and pretreatment egg counts.

Preliminary study of urinary schistosomiasis in a village in the delta of the Senegal river basin, Senegal.

Three years after the first cases of urinary schistosomiasis infection were reported in the village of Mbodiene, Senegal, Schistosoma haematobium eggs were found in 87% of the inhabitants of this village; 30% were heavily infected (> 50 eggs per 10 mL urine). The prevalence of infection was very high in all age groups, but children showed more intense infections. No difference between sexes was found. In the special situation of a very high prevalence, test strips for proteinuria and haematuria are not very useful for the individual diagnosis of S. haematobium infection. Six and 12 weeks after treatment with a single dose of praziquantel (40 mg/kg), S. haematobium eggs were found in 25% and 30% of the treated subjects, respectively. Bulinus globosus was identified as intermediate host, but other snail vectors may also play a role. S. mansoni eggs were found in 1% of the population. Both S. haematobium and S. mansoni are spreading in the delta of the Senegal river.

Evaluation of ultrasonographic staging systems for the assessment of Schistosoma mansoni induced hepatic involvement.

For the sonographic assessment and grading of hepatosplenic morbidity induced by Schistosoma mansoni infection, several quantitative and qualitative classification systems have been used. In an attempt to evaluate two staging systems, a study was performed as part of a schistosomiasis research and control programme in Richard Toll, Senegal. A total of 700 residents of the township N'diangué were parasitologically, clinically and sonographically examined in July 1993. Two ultrasound observers (M.D. and E.D.) applied the Cairo and the Managil classification (E.D. only) for the grading of periportal thickening of the liver. In spite of high prevalence and intensity of infection, severe hepatic morbidity was rare. According to the Cairo classification, there was a high percentage of subjects with grade I periportal thickening, with considerable inter-observer variability. In the Cairo classification, which is based on the diameter of peripheral portal vein branches, firm cut-offs are used, independent of body height. We show the relationship between body height and portal vein diameters and recommend the use of body height-dependent reference values to avoid falsely high percentages of periportal thickening, especially in children. To minimize inter-observer variability, a clarification of existing instructions for taking measurements for grading is suggested. These suggestions have been considered during the follow-up expert meeting on the Cairo classification in Niamey under the auspices of the World Health Organization in October 1996.