focal dermal hypoplasia ( fdh ) is a comparatively rare multisystem disorder , characterized by meso - ectodermal dysplasia of genetic origin . it is more commonly referred to as goltz syndrome , as goltz et al . in 1962 it is believed to be inherited as an x - linked dominant disorder with in utero lethality for homozygous males . though cutaneous manifestations predominate ( evident from the name fdh ) , characteristic abnormalities are frequently encountered in the eyes , bones , hair , nails , and practically every system of the body . here , we report a newborn female with ectrodactyly and characteristic skin lesions of goltz syndrome . a one - day - old female baby born out of a nonconsanguineous marriage with a birth weight of 2 kg was admitted in our nursery with multiple congenital anomalies . , there were patchy areas of absent skin cover over the periumbilical region , right - sided inguinal region , and back of the right thigh . a few atrophic areas of skin with alternate hypo and hyperpigmented lines in reticular pattern were noted over the right lateral chest wall and both the pinnas [ figure 1 ] . the face was triangular in shape with a broad nasal bridge , pointed chin , and thin , broad ears . atrophic skin lesions , aplasia cutis congenita , ectrodactyly with true shortening of right lower limb , and syndactyly of right first and second fingers the right lower limb was grossly shorter than the left one with a characteristic lobster claw deformity , otherwise known as ectrodactyly . also , there was presence of syndactyly of the first and second fingers of the right hand [ figure 1 ] ophthalmological examination revealed bilateral coloboma of the iris at the mid - periphery ( right > left ) . x - ray of the right hand showed fused first and second metacarpals , whereas skiagram of the right lower limb revealed the absence of the fibula and all other bones distal to it , i.e. tarsals , metatarsals , and phalanges [ figure 2 ] . cranial ultrasound and echocardiography were within normal limits , but abdominal ultrasonography showed bilateral hydronephrosis and hydroureter . hence , she was discharged from the hospital with a plan for close follow - up with a multidisciplinary approach . follow - up at 1 month of age revealed that the atrophic skin lesions had further extended to involve larger areas of the trunk with a more characteristic appearance [ figure 3 ] . follow - up ultrasonography ( usg ) at 3 months showed regression of hydronephrotic changes . skiagram of the lower limbs showing absence of right fibula and all other bones distal to it , i.e. tarsals , metatarsals , and phalanges follow - up at 1 month of age revealing that atrophic skin lesions have further extended to involve larger areas of trunk with a more characteristic appearance fdh can involve all the three layers , i.e. ectoderm ( skin , eyes ) , mesoderm ( bones , teeth ) , and endoderm ( various mucosae ) with variable expression . variation in clinical severity is said to be partly due to lyonization of the x chromosome and partly because of postzygotic genomic mosaicism , which is also responsible for the sporadic cases ( 95% ) . heterozygous and mosaic mutations in the porcn gene of the x chromosome at the xp11.23 locus are now well - proven etiology for the pathogenesis of fdh . although the biochemical functions of the porcn gene have not been completely characterized , it is known to target wnt signaling proteins that are the key regulators of embryonic development of the skin , bone , and other structures . though it is an x - linked dominant disorder mainly affecting females , reports of alive males represent cases of sporadic new mutations or somatic mosaicism , and such cases the predominant feature of fdh is connective tissue dysplasia , particularly of the skin and skeletal system . histopathology of the atrophic and lipomatous skin reveals marked reduction in the thickness of the dermis . collagen fibers are attenuated and fat cells extend virtually up to the epidermis ; thin strands of dermal connective tissue may be interspersed . skin involvement is usually in the form of asymmetrical linear streaks of atrophy and telangiectasia , which follow blaschko 's lines . in racially pigmented skin , soft , pinkish - yellow to brown saccular nodules ( fat herniations ) provide the second characteristic type of skin lesion . other characteristic cutaneous findings include raspberry papillomas , present mostly at the junction of skin and mucosa , around lips , or the vulvar and perianal areas . however , complete absence of skin in the form of aplasia cutis congenita has been reported rarely , which was the initial skin manifestation in our case . now , aplasia cutis congenita ( acc ) encompasses a heterogeneous group of disorders characterized by localized defects of skin that may occur anywhere on the body . though the scalp is the most common site , it involved periumbilical area and the back of the thigh in this case . musculoskeletal anomalies include characteristic facies , as described in our case , and asymmetric involvement of the hands and feet in 60% of the patients , including syndactyly , ectrodactyly , polydactyly , absence or hypoplasia of digits , and even absence of an extremity . our patient had multiple skeletal anomalies like syndactyly , ectrodactyly and asymmetry of limbs with absence of multiple bones , both long and short , of the right lower limb . other systems are also known to be frequently involved , of which gastro - intestinal and renal systems are of prime importance . there were a few reports about the presence of ectopic kidney , hypoplastic kidney or absent kidney , but association of bilateral hydronephrosis and hydroureter is rarely reported in the literature . the most common differential diagnoses are midas ( microphthalmia , dermal aplasia , sclerocornea ) , incontinentia pigmenti , rothmund  thomson syndrome , adams oliver syndrome , nevus lipomatosus superficialis , aplasia cutis and ectrodactyly ectodermal dysplasia clefting ( eec ) syndrome . so , to conclude , with timely diagnosis of complications and appropriate supportive care , majority of the patients can lead a normal life with adequate development and mentation , except a few unlucky ones with severe forms of affection . we are reporting a rare case of goltz syndrome with aplasia cutis congenita as the initial cutaneous manifestation and bilateral hydronephrotic kidney , both of them being quite rare .
goltz syndrome or focal dermal hypoplasia is a rare multisystem disorder , involving all the three germ cell layers . 
 the disease is thought to be inherited in x - linked dominant fashion with heterogeneous mutations of the porcn gene at xp11.23 locus . 
 majority of the cases are sporadic , mainly due to postzygotic somatic mutations . 
 the clinical spectrum includes characteristic cutaneous manifestations , multiple skeletal anomalies , and involvement of the eyes , hair , nails , kidneys , and so on . 
 considerable variability is noted in the clinical expression of the disease probably due to genomic mosaicism . around 300 cases of goltz syndrome 
 have been reported in the literature . here , we report such a case with characteristic skin lesions , multiple bony defects , distinctive facial features , coloboma of iris , and bilateral hydronephrosis . the diagnosis was evident immediately after birth due to the characteristic clinical picture of the baby .