williams  beuren syndrome ( wbs ) is one of the most common recurrent microdeletion syndromes , with an estimated incidence varying from 1 in 7500 to 1 in 20,000 births 1 , 2 . patients can be recognized clinically , given their characteristic features , encompassing congenital heart defect , typically supravalvular aortic stenosis ( svas ) and/or peripheral pulmonic stenosis , short stature / growth retardation , recognizable facial dysmorphism , developmental delay and intellectual disability , distinct behavioral phenotype ; and , in some instances , hypercalcemia . facial dysmorphism includes a wide mouth , short nose with bulbous or upturned nasal tip , long philtrum , thick everted vermillion of the lips , bitemporal narrowing , periorbital fullness , full cheeks , small jaw , and the characteristic stellate pattern of the iris 3 , 4 . the cognitive profile in wbs ranges from mild to severe i d 3 , 5 , 6 . although acquisition of language is often delayed in wbs patients , they later develop good language skills and become talkative 7 , 8 . behavioral issues in wbs comprise anxiety , hyperacousis , attention problems , hypersociability or friendly behavior , and strong affinity and interest to music 7 , 9 , 10 . some cases are more difficult to diagnose , since they present with atypical features 11 , or because they have a different ethnicity where the features may be different from those observed in caucasians . for instance , african patients with wbs from cameroon have been reported with incomplete wbs facial dysmorphism 8 . finally , cases with a deletion smaller or larger than the recurrent 1.5 mb 7q11.23 microdeletion may also present with a milder or more severe phenotype 12 . we here report a wbs patient from central africa carrying the recurrent wbs microdeletion who presented with a typical facial dysmorphism but more severe intellectual disability and atypical behavioral phenotype due to a confounding factor , that is , meningitis with coma supposedly resulting in brain damage . an 8.2 years old congolese boy was referred by his pediatrician to the genetic clinic at the university hospitals of the university of kinshasa , dr congo , for evaluation of intellectual disability , allegedly resulting from an episode of meningitis and coma . he was born from unrelated , healthy parents after an uneventful pregnancy and delivery . at the age of 2 years , he was n't able to standup without support or build simple sentences although he could call names of his relatives . four months later , he suffered from meningitis and remained in coma for 2 days . his behavior changed , including hyperactivity , irritability , hypersensitivity to noise and episodes of aggressiveness against strangers . in contrast , he was friendly toward familiar persons and demonstrated a strong attraction to music and musical sounds . he was diagnosed with sequels from meningitis and was followed by a neurologist until the age of 8 years , when he was referred for a genetic evaluation . at that time , he had severe global growth delay with microcephaly ( ofc 47 cm ; 3.82 sd ) , short stature ( length 109 cm ; 3.43 sd ) and low weight ( 17 kg ; < 3 sd ) . family history revealed that two siblings of the patient ( fig there were two other males with i d in the pedigree , related through their mothers . patient 's phenotype consisted of a triangular face with low set ears , long philtrum , flat nose bridge , bulbous nose tip , anteverted nostrils , pronounced nasolabial folds , large mouth , thick and everted vermillion of the upper and lower lip , and a small jaw ( fig . 1 , lower panel ) . he also had widely spaced nipples , a small penis , bilateral cryptorchidism , and deep palmar creases . ( a ) pedigree showing three males with i d , consistent with the xlinked inheritance ; ( b ) clinical features . note triangular face with low set ears , long philtrum , flat nasal bridge , bulbous nose tip , anteverted nostrils , pronounced nasolabial folds , large mouth , thick and everted vermillion of the upper and lower lip and a small jaw , widely spaced nipples , and deep palmar creases . although the pedigree was consistent with xlinked i d , a clinical diagnosis of wbs was retained . fluorescent in situ hybridization ( fish ) was performed on nuclei from peripheral white blood cells using the commercially available vysis lsi eln kit ( vysis ; abbott laboratories , abbott park , il ) . a total of 100 nuclei were examined and a single eln was observed in all of them , whereas the control probe always showed two signals . microarraycgh was performed using a stripped cytosure isca v2 array 8  60 k format ( ogt , oxford uk ) slide , the cytosure genomic dna labelling kits ( oxford , uk ) , and the oligo acgh & chiponchip hybridization kits ( agilent , santa clara , ca ) following manufacturers procedures . this revealed the presence of a recurrent 1.57 mb deletion arr[hg19]7q11.23 ( 72,634,87474,203,685)1 ( fig . ( a ) two interphase nuclei showing a single signal for the elastin probe ( red ) and two signals for the control probe ( green ) ; ( b ) chromosome icon and the zoomin on the deleted region . we report on a central african patient with typical gestalt for wbs . retrospectively , we uploaded facial photographs of the patient to face2gene ( http://www.fdna.com/face2gene/ ) . basically , this tool captures gestalt signatures from patient 's facial photograph and compares these to patients in the database , then reports the 10 most likely matches . it is surprising that the patient was only diagnosed at age 8.2 years , despite the typical facial appearance . mean age of diagnosis for wbs in western countries is 3.5 years 13 , 14 . first , the facial dysmorphism in wbs evolves over age and may be discrete in infancy and early childhood 4 , 13 , 14 . second , our patient had no svas , one of the most characteristic features often leading to the diagnosis 13 , 15 . finally , severe phenotypes have been associated with larger deletions . as the deletion in our patient corresponds to the classical wbs microdeletion , we assume that the severe speech deficit and profound intellectual disability in the patient are more likely the complications of the meningitis and coma . it is thus undeniable that an acquired condition modified the clinical course of the patient toward the more severe and atypical phenotype for wbs causing the delay in diagnosis . such overlap of genetic disease with an infectious disease is expected to be frequent in the developing world , where infections represent the major medical problem . as previously reported , infections are major cause for misdiagnosis of genetic diseases in developing countries 16 . the present report supports the assumption that infections constitutes a major pitfall for genetic diagnosis and warns for clinicians working in developing world that a genetic disease may be masked by a intercurrent infectious disease . to date given the incidence of 1/7500 for wbs 2 , this suggests that most cases remain undiagnosed . this is most likely due to a lack of training in the field of dysmorphology and lack of access to genetic facilities in that part of the world .