Congenital anomalies of kidney and hand: a review

Critical COVID-19 in a pregnant patient who presented in starvation ketoacidosis with a background history of acrorenal syndrome

A primiparous woman in her late 30s at 28+1 weeks’ gestation presented with a 3-day history of abdominal pain, loss of appetite, nausea and vomiting and was diagnosed with starvation ketoacidosis. A routine admission swab returned positive for COVID-19. She had been diagnosed with acrorenal syndrome from birth. Three days post admission, she deteriorated rapidly into respiratory failure requiring intubation and ventilation. She was treated with dexamethasone, prophylactic enoxaparin, a course of piperacillin/tazobactam followed by meropenem and fluconazole and 8 cycles of proning. An emergency caesarean section was performed on day 12 of hospital admission at 29+5 weeks’ gestation to improve maternal oxygenation and ventilation. The baby had deformities consistent with acrorenal syndrome but no evidence of COVID-19. She spent 23 days in the intensive care unit. Our case describes an unusual presentation of COVID-19, the challenges in managing critically ill pregnant patients along with a rare background history of acrorenal syndrome.

Renal and Skeletal Anomalies in a Cohort of Individuals With Clinically Presumed Hereditary Nephropathy Analyzed by Molecular Genetic Testing

Background: Chronic kidney disease (CKD) in childhood and adolescence occurs with a median incidence of 9 per million of the age-related population. Over 70% of CKD cases under the age of 25 years can be attributed to a hereditary kidney disease. Among these are hereditary podocytopathies, ciliopathies and (monogenic) congenital anomalies of the kidney and urinary tract (CAKUT). These disease entities can present with a vast variety of extrarenal manifestations. So far, skeletal anomalies (SA) have been infrequently described as extrarenal manifestation in these entities. The aim of this study was to retrospectively investigate a cohort of individuals with hereditary podocytopathies, ciliopathies or CAKUT, in which molecular genetic testing had been performed, for the extrarenal manifestation of SA.

Material and Methods: A cohort of 65 unrelated individuals with a clinically presumed hereditary podocytopathy (focal segmental glomerulosclerosis, steroid resistant nephrotic syndrome), ciliopathy (nephronophthisis, Bardet-Biedl syndrome, autosomal recessive/dominant polycystic kidney disease), or CAKUT was screened for SA. Data was acquired using a standardized questionnaire and medical reports. 57/65 (88%) of the index cases were analyzed using exome sequencing (ES).

Results: 8/65 (12%) index individuals presented with a hereditary podocytopathy, ciliopathy, or CAKUT and an additional skeletal phenotype. In 5/8 families (63%), pathogenic variants in known disease-associated genes (1x BBS1, 1x MAFB, 2x PBX1, 1x SIX2) could be identified.

Conclusions: This study highlights the genetic heterogeneity and clinical variability of hereditary nephropathies in respect of skeletal anomalies as extrarenal manifestation.

Two Cases of Preaxial Polydactyly of the Foot: Important Implications for Plastic Surgeons

Although polydactyly is quite common in general, preaxial polydactyly of the foot is rare (0.4 per 10,000 patients) and specifically associated with certain congenital abnormalities and syndromes, which can include craniosynostosis, corpus callosum agenesis, and renal malformations. We present 2 recent cases of preaxial polydactyly of the foot that highlight the importance of maintaining a high level of suspicion for associated abnormalities in these patients. The first patient, who presented with supernumerary preaxial digits on both feet, pre- and postaxial polydactyly of the hands, was also macrocephalic and hyperteloric; this presentation strongly suggested a diagnosis of Greig cephalopolysyndactyly, a GLI3-variant syndrome. The second patient, who had 2 preaxial digits on one foot, was found to also have a horseshoe kidney, a malformation that has been associated with limb defects as part of an acrorenal syndrome. These cases emphasize the importance of a thorough clinical approach to patients with preaxial polydactyly of the foot. Although many patients with this anomaly may be well known to geneticists, a child may be referred to a plastic surgeon for reconstruction of what is thought to be an isolated cosmetic or local functional issue. Plastic surgeons should be aware of the complex nature of preaxial polydactyly of the foot and potential syndromic presentation.

Pollicization of Middle Finger in a Cleft Hand Associated with Acrorenal Syndrome

Introduction Acrorenal syndrome is autosomal recessive inherited disorder commonly associated with congenital renal disorders and ipsilateral hand/foot anomalies. The hand and foot deformities corrections are challenging to achieve a good functional and cosmetic result. We described a case of acrorenal syndrome with suppressed radial elements and absent thumb in whom we were able to reconstruct the hand.

Case Report A 5-year-old girl presented to us with right renal agenesis and right hand/foot deformity. The hand showed a cleft hand with central deficiency, index finger hypoplastic, and syndactylyzed to middle finger, absent thumb. The hand was nonfunctional because of absent thumb. To improve the functions, it was decided to proceed with thumb reconstruction. The middle finger was pollicized to regain tripod grip and thereby the functions was enhanced.

Discussion The cleft hand belongs to “failure of finger ray induction group” in classification by “International Federation of Societies for Surgery of the Hand (IFSSH).” Absence of thumb and first web space makes it a strong indication for surgical reconstruction. In our case, thumb was addressed by pollicization of middle finger and we were able to provide a good tripod grip.

Ectopias of the kidney, urinary tract organs, and male genitalia

The most frequent anomaly of the urogenital tract is a simple renal ectopia with one organ lying in the pelvis. Crossed renal ectopia is a less common condition in which the ectopic kidney is located on the opposite side of the midline from the ureteral insertion in the urinary bladder. The cause of both types of renal ectopia is the arrest or failure of the kidney ascent from the pelvic to the lumbar position. Whereas an accelerated ascent leads to a subdiaphragmal or intrathoracic ectopic position, an ectopic ureter can be defined as one that does not drain into the trigonum vesicae. The ectopic orificium can be located situated in the bladder neck and urethra as well as somewhere in the genital area.Exstrophy of the urinary bladder is not a complete ectopia. Because the abdominal wall and the anterior part of the bladder wall are lacking, the bladder mucosa grows directly into the skin. The complex exstrophy of the bladder and intestine corresponds to a cloacal exstrophy, in which the bladder is split in two halves on either side of the gut portion. Testicular ectopia refers to the location of the testis in a position outside of its normal course of descent.Prostatic ectopia does not refer to the wrong location of the entire organ, but to a scattered group of prostate glands, which are mostly found in the submucosal part of the urinary bladder or proximal urethra. Other described locations are the intestinal wall, anus, pericolic fat tissue, spleen, seminal vesicle, testis, and cervix uteri.The associated ectopic penis, scrotum, and penoscrotal transposition are the least common and probably the absolutely most unknown malformations of the male genitalia. The ectopic penis and scrotum are located in the perineum, whereas in the transposition the penis lies above the scrotum.

[Ectopias of the kidney, urinary tract organs, and male genitalia. German version.]

The most frequent anomaly of the urogenital tract is a simple renal ectopia with one organ lying in the pelvis. Crossed renal ectopia is a less common condition in which the ectopic kidney is located on the opposite side of the midline from the ureteral insertion in the urinary bladder. The cause of both types of renal ectopia is the arrest or failure of the kidney ascent from the pelvic to the lumbar position. Whereas an accelerated ascent leads to a subdiaphragmal or intrathoracic ectopic position, an ectopic ureter can be defined as one that does not drain into the trigonum vesicae. The ectopic orificium can be located situated in the bladder neck and urethra as well as somewhere in the genital area.Exstrophy of the urinary bladder is not a complete ectopia. Because the abdominal wall and the anterior part of the bladder wall are lacking, the bladder mucosa grows directly into the skin. The complex exstrophy of the bladder and intestine corresponds to a cloacal exstrophy, in which the bladder is split in two halves on either side of the gut portion. Testicular ectopia refers to the location of the testis in a position outside of its normal course of descent.Prostatic ectopia does not refer to the wrong location of the entire organ, but to a scattered group of prostate glands, which are mostly found in the submucosal part of the urinary bladder or proximal urethra. Other described locations are the intestinal wall, anus, pericolic fat tissue, spleen, seminal vesicle, testis, and cervix uteri.The associated ectopic penis, scrotum, and penoscrotal transposition are the least common and probably the absolutely most unknown malformations of the male genitalia. The ectopic penis and scrotum are located in the perineum, whereas in the transposition the penis lies above the scrotum.

Microarray analysis in pregnancies with isolated unilateral kidney agenesis

BackgroundThe objective of our study was to examine the risk for submicroscopic chromosomal aberrations among fetuses with apparently isolated solitary kidney.MethodsData acquisition was performed retrospectively by searching Israeli Ministry of Health-computerized database. All cases having chromosomal microarray analysis (CMA), referred because of an indication of isolated unilateral kidney agenesis between January 2013 and September 2016, were included. Rate of clinically significant CMA findings in these pregnancies was compared to pregnancies with normal ultrasound, based on a systematic review encompassing 9,792 cases and local data of 5,541 pregnancies undergoing CMA because of maternal request.ResultsOf the 81 pregnancies with isolated solitary kidney, 2 (2.47%) loss-of-copy number variants compatible with well-described deletion syndromes were reported (16p11.2-16p12.2 and 22q11.21 microdeletion syndromes). In addition, one variant of unknown significance was demonstrated. The relative risk for pathogenic CMA findings among pregnancies with isolated unilateral renal agenesis was not significantly different compared with the control population.ConclusionCMA analysis in pregnancies with unilateral renal agenesis might still be useful, to the same degree as it can be in the general population.

A Gene Implicated in Activation of Retinoic Acid Receptor Targets Is a Novel Renal Agenesis Gene in Humans

Renal agenesis (RA) is one of the more extreme examples of congenital anomalies of the kidney and urinary tract (CAKUT). Bilateral renal agenesis is almost invariably fatal at birth, and unilateral renal agenesis can lead to future health issues including end-stage renal disease. Genetic investigations have identified several gene variants that cause RA, including EYA1, LHX1, and WT1 However, whereas compound null mutations of genes encoding α and γ retinoic acid receptors (RARs) cause RA in mice, to date there have been no reports of variants in RAR genes causing RA in humans. In this study, we carried out whole exome sequence analysis of two families showing inheritance of an RA phenotype, and in both identified a single candidate gene, GREB1L Analysis of a zebrafish greb1l loss-of-function mutant revealed defects in the pronephric kidney just prior to death, and F0 CRISPR/Cas9 mutagenesis of Greb1l in the mouse revealed kidney agenesis phenotypes, implicating Greb1l in this disorder. GREB1L resides in a chromatin complex with RAR members, and our data implicate GREB1L as a coactivator for RARs. This study is the first to associate a component of the RAR pathway with renal agenesis in humans.

Unusual Presentation of Duplex Kidneys: Ureteropelvic Junction Obstruction

Aim. Ureteropelvic junction obstruction (UPJO) is rarely associated with a duplex collecting system. We review this unusual anomaly in terms of presentation, diagnostic evaluation, and surgical management. Method. We retrospectively reviewed the medical records of patients diagnosed with a duplex system with UPJO. Result. Sixteen patients (6 girls, 10 boys) with 18 moieties were treated surgically and four patients were treated conservatively. The median age at surgery was two years (range, 2 months to 7 years). The lower pole and upper moiety were affected in 12 and two kidneys, respectively, and both were affected in two patients. The anomaly was right-sided in 12 moieties and left-sided in six. The duplication was incomplete in seven patients and complete in nine. The mean renal pelvis diameter at the time of surgery was 25.6 (range 11-48 mm) mm by USG. The mean renal function of the involved moiety was 28.3% before surgery. Management included pyelopyelostomy or ureteropyelostomy in six moieties, dismembered pyeloplasty in eight moieties, heminephrectomy in four cases, and simultaneous upper heminephrectomy and lower pole ureteropyelostomy in one patient. Conclusion. There is no standard approach for these patients and treatment should be individualized according to physical presentation, detailed anatomy, and severity of obstruction.