Author(s): Abhinav Gupta, Mohd and Iqbal Bhat
ABSTRACT: Acral (limb) and renal anomalies occur together as a single developmental field defect or as components of several malformation syndromes. The embryogenesis of that defect was studied experimentally by Lash and the developmental relationship between kidneys and limbs has been reviewed by Buchta and Gilbert. The acral anomalies consist of split hand/ split foot, varying combination of oligodactyly, ectrodactyly, syndactyly, brachydactyly, polydactyly or fusion of carpal, tarsal, metatarsal bones of hands and feet. Urinary tract dysplasias are renal agenesis, duplication, ureteral hypoplasia, polycystic kidneys, hydronephrosis and bladder neck obstruction. The authors report three cases of acrorenal syndrome and discuss its clinical and laboratory findings.
Acral (limb) and renal anomalies occur together as a single developmental field defect or as components of several malformation syndromes. The embryogenesis of that defect was studied experimentally by Lash [1]. and the developmental relationship between kidneys and limbs has been reviewed by Buchta and Gilbert [2,3]. The acral anomalies consist of split hand/ split foot, varying combination of oligodactyly, ectrodactyly, syndactyly, brachydactyly, polydactyly or fusion of carpal, tarsal, metatarsal bones of hands and feet. Urinary tract dysplasias are renal agenesis, duplication, ureteral hypoplasia, polycystic kidneys, hydronephrosis and bladder neck obstruction. The authors report three cases of acrorenal syndrome and discuss its clinical and laboratory findings. The association of limb deformities and renal malformations has been described in different reports under the term acrorenal syndrome [4-8]. The renal anomalies vary from mild anatomical malformations to severe renal hypoplasia and renal failure [4]. The underlying renal pathology associated with renal failure has mainly been described as oligomeganephronia [4-10]. Presentation with end-stage renal failure is rarely reported [6-11].
A 10 year old consanguineous male presented to ASCOMS Hospital, Jammu with severe left flank pain and reduced urine output. On physical examination, in addition to left costovertebral angel tenderness, an extra thumb on bilateral hands and few external skin tags on his ears were prominent as a congenital anomaly. His genitourinary examination revealed a pair of completely descended normal appearing testis. Skeletal survey showed congenital reduction deformities of both feet. Abdominal ultrasonography revealed bilaterally small kidneys with altered CMD. The bipolar measurement of right kidney was 4.5cm and left kidney as 4.3cm. There was no similar history in his family. On investigation, Haemoglobin was 9 gm/dl, TC of WBC was 13000/mm, platelet count 160000/mm [3]. Serum creatinine was 3 mg/dl, sodium was 134 mEq/L, potassium was 4.8 mEq/L. His visual acuity and fundus examination was reported to be normal. His echocardiography revealed no significant heart anomalies. He was managed on the lines of chronic kidney disease and is being followed up with renal function tests periodically.
Figure 1: Showing Polydactly
Figure 2: Showing Radiologic Evidence of Polydactly
Figure 3: Showing External Ear Tags
A 46 year old diabetic female presented to ASCOMS HOSPITAL, Jammu with severe left flank pain, swelling of bilateral lower limbs and reduced urine output. The findings on physical examination included left costovertebral angle tenderness, bilateral pedal edema, presence of extra toe. Intellectual development was normal as per age. Skeletal survey revealed polydactyly in right foot and right hand. Laboratory investigations revealed: urea 140 mg/dl, creatinine 4 mg/dl, sodium 136 meq/l, potassium 4.6 meq/l, calcium 9 mg/dl, phosphorus 6.8mg/dl, hemoglobin 6.1 g/dl, WBC Count of 9800/mm and HbA1C 7.1%. Abdominal ultrasonography showed a normal liver, enlarged spleen (19 cm) and multiple calculi in both kidneys, largest in right kidney measuring 7.2 mm and largest in left kidney measuring 11 mm with no hydroureteronephrosis. Bipolar measurement of the right kidney was 8.9cm and left kidney 8.3 cm. Her Echocardiogram was normal. Deformed hands and feet were noticed immediately after birth, but no major illnesses were reported in the first 3 years of life. Thereafter, she was noticed to have bilateral vision loss and fundus examination which was done later revealed pigmentary retinopathy. Surgical opinion was sought for nephrolithiasis and she was managed conservatively with blood transfusion and adequate hydration with close follow up of renal function tests.
Figure 4: Showing Polydactly of Feet
An 8 year old non-consanguineous male child, mainly asymptomatic apart from mild persistent abdominal pain presented with his abdominal ultrasonography revealing non visualised right kidney in right renal fossa or any other ectopic location and a normal appearing left kidney with the bipolar measurement of 9.8 cm. The abdominal examination was consistent with the ultrasonographic findings as no renal mass could be palpated on bimanual palpation on the right side. However, the left kidney was normally palpated. His general physical examination revealed few hypopigmented macular areas on his face and neck. His skeletal survey showed congenital malformations of hands and feet. Deformed hands and feet were noticed right after birth but no major illnesses were reported till 4 years of age. Thereafter, he appeared to be lethargic and pale. His IQ is however normal for his age. Thorough history taking revealed right undescended testis that had been surgically corrected at 2 years of age. There were no similar renal or skeletal abnormalities in his family. His visual acuity and fundus examination was normal. His investigations showed Hemoglobin of 9.2 g/dl, WBC count of 7800/mm creatinine of 1.9 mg/dl, urea of 54 mg/dl, sodium 138 meq/l, potassium of 4.0 meq/l. His echocardiogram was normal. He is currently being managed symptomatically with a close follow up of renal function tests.
Figure 5: Showing Malformation of Hands
Acrorenal syndrome has been described by different observers since the detailed description of Curran and Curran [11]. reported the severe limb deformities being common to all reported cases [4-7]. The lower limbs were more severely affected than the upper limbs in the majority of cases described. The pathogenesis has been linked to an abnormal epithelial-mesenchymal interaction during embryonic development [12]. Such interaction is crucial to the formation of the apical-ectodermal ridge subsequent limb development and to the development of ureteric bud. This is also involved in the morphogenesis of the palate, jaw, skin derivatives, the mammary glands, the paramesonephric ducts and the eye. Zeier et al. [8] reported an adult with acrorenal syndrome in whom the limb defects were more in the upper than the lower limbs. Renal involvement in our patients was severe, as in other cases studied. In our patients, the upper and lower limb defects were equal in incidence and severity. The reported renal involvement in acrorenal syndrome varies from mild hydronephrosis with duplex system to severe bilateral renal hypoplasia and renal failure. Renal pathology has not been frequently described, but the majority of patients who had renal biopsies had oligomeganephronia [7,8,10]. Oligomeganephronia is associated with extremely small kidneys; the kidneys of our patients were also severely hypoplastic [9].
Cryptorchidism and hypospadias are common associations with other renal anomalies and present in about 50% of males with acrorenal syndrome [8,11].
