Renal agenesis can develop as a component of a syndrome or as an isolated anomaly [1]. This congenital disorder is classified as unilateral or bilateral.

Unilateral renal agenesis

Renal agenesis is commonly unilateral with a predilection for males [2]. Individuals with only one kidney will likely remain asymptomatic [3] and achieve a normal life expectancy. Typically, the sole kidney enlarges to compensate for the absent kidney. This disorder is usually discovered incidentally.

Among the various urologic pathologies that are observed in patients with unilateral renal agenesis, contralateral vesicoureteral reflux is most frequent [4].

Bilateral renal agenesis

Babies with this type of renal agenesis will die in utero or within a few hours of life due to immature lungs and consequently respiratory failure [5]. These patients lack the complete development of kidneys and ureters and hence manifest with the interrelated complications of pulmonary hypoplasia and oligohydramnios.

Regarding the clinical presentation, patients exhibit the Potter sequence, which is characterized by extrarenal features such as wide-set eyes, epicanthal folds, flat nose, large low-set ears with absent cartilage, receding chin, and limb defects [6] [7]. Furthermore, there may be other systems that are involved in Potter syndrome. Among these are cardiac malformations [8] and abnormalities of the gastrointestinal [5] and genitourinary [9] tracts.

Pregnancy complications

A fetus with renal agenesis is at risk for intrauterine growth retardation (IUGR), breech presentation, and premature delivery.

• Asymptomatic

  Patients with HWW syndrome are usually asymptomatic until menarche, when they present with acute lower abdominal pain. Here we report a case of a female newborn with right renal agenesis diagnosed during the pregnancy. [ncbi.nlm.nih.gov]

  Individuals with only one kidney will likely remain asymptomatic and achieve a normal life expectancy. Typically, the sole kidney enlarges to compensate for the absent kidney. This disorder is usually discovered incidentally. [symptoma.com]

  URA may be asymptomatic but sometimes the other kidney may be hypertrophied and more susceptible to damage due its size. Top of the page WEST MIDLANDS DATA Information to follow Top of the page [perinatal.nhs.uk]

  He was completely asymptomatic, although he experienced gross hematuria 10 months before his visit. [ci.nii.ac.jp]

• Anemia

  Anemia is also treated with iron supplements, which can be given orally or administered through an injection. [encyclopedia.com]

  Complete blood count may reveal anemia due to deficiency of erythropoietin. Diagnostic Test Results-Imaging Maternal sonography reveals oligohydramnios along with nonvisualization of fetal kidneys, ureters, and bladder, confirming BRA. [quizlet.com]

  There are several multi-organ syndromes associated with renal agenesis and hypoplasia: Miller-Dieker syndrome DiGeorge syndrome Brachio-oto-renal syndrome Fanconi anemia Fraser syndrome Kallmann syndrome Klinefelter syndrome Rokitansky-Küster-Hauser syndrome [clinicaladvisor.com]

  前立腺特異抗原 proteinuria蛋白尿 proximal tubule近位尿細管 psychological精神的な puberty思春期 pudendal外陰部の pudendal nerve 陰部神経 pyelonephritis腎盂腎炎 pyeloplasty腎盂形成術 pyuria膿尿 r rapidly progressive glomerulonephritis急性進行性糸球体腎炎 reflux nephropathy逆流性腎症 renal abscess腎［臓］膿瘍 renal anemia [tokyo-med.ac.jp]

• Fever

  OHVIRA may present as abnormal vaginal discharge, infertility, vomiting, and fever. [omicsonline.org]

  Babies and children with UTIs may become irritable, have a fever, have pain on weeing, feel sick or be sick. If your child has a UTI, he or she will need to take antibiotics, medicines that kill the germs. [infokid.org.uk]

  He did not have a family history of similar illness, head trauma in the past, or fever. Neuroimaging or electroencephalography (EEG) was not performed previously. His vital parameters were within the normal range, except that he had tachycardia. [annalsofian.org]

  She was admitted four months later with severe abdominal pain, especially in the lower quadrants without fever, vomiting, diarrhea or urinary symptoms. On physical examination vital signs were normal, and there was no palpable abdominal mass. [scielo.mec.pt]

• Poor Growth

  While the exact cause is unknown, unilateral renal agenesis is more common with intrauterine growth restriction (poor growth during pregnancy) and in multiples (twins, triplets, etc.). [childrenscolorado.org]

  Unilateral renal agenesis is more common with intrauterine growth retardation (poor growth during pregnancy) and often results in premature birth. [health.state.mn.us]

  Children with chronic renal failure often have poor growth and require supplemental human growth hormone (Genotropin, Humatrope, Nutropin). Human growth hormone stimulates the growth of bone, skeletal muscle, and organs. [encyclopedia.com]

• Fishing

  Unilateral and bilateral renal agenesis in humans, mice and zebra fish has been linked to mutations in the gene GREB1L. It has also been associated with mutations in the genes RET or UPK3A. in humans and mice respectively. [en.wikipedia.org]

  The human, mouse, and fish variants (position indicated in human protein) encode proteins that are altered in the conserved c-terminus of the protein. [doi.org]

• Respiratory Distress

  If a neonate with bilateral renal agenesis has severe respiratory distress from severe pulmonary hypoplasia, no further treatment may be the decided course of action. [encyclopedia.com]

  Provide appropriate respiratory care measures. Offer assistance of pastoral care or of a religious support person to assist with grieving. [quizlet.com]

  Review Topic QID: 101903 M1 Select Answer to see Preferred Response PREFERRED RESPONSE 4 Sorry, this question is for PEAK Premium Subscribers only (M1.EB.70) A child is born by routine delivery and quickly develops respiratory distress. [medbullets.com]

• Respiratory Insufficiency

  Leg deformity (excessive flexion of hip and knees) Respiratory insufficiency Anuria and increasing retention parameters Diagnosis of Potter's Syndrome Maternal ultrasound screening: oligohydramnios and no kidney tissue visible. [urology-textbook.com]

  The cause of death is pulmonary hypoplasia, with consequent respiratory insufficiency. There are rare cases in which a portion of one kidney has formed and some lung development occurs. These cases are also often fatal. [encyclopedia.com]

• Diarrhea

  Página 54 - Pedigree demonstrating a sex-linked recessive condition characterized by draining ears, eczematoid dermatitis and bloody diarrhea. ‎ Página 51 - Selective IgA deficiency: presentation of 30 cases and a review of the literature. ‎ [books.google.es]

  She was admitted four months later with severe abdominal pain, especially in the lower quadrants without fever, vomiting, diarrhea or urinary symptoms. On physical examination vital signs were normal, and there was no palpable abdominal mass. [scielo.mec.pt]

• Hypertension

  We report on the association of renal agenesis, renal arteriovenous fistulae, fibromuscular dysplasia and vertebral body anomaly in a young female patient with renovascular hypertension. [ncbi.nlm.nih.gov]

  High blood pressure People with only one kidney have a slightly higher risk of hypertension, blood pressure that is too high. If your child has hypertension, he or she will need to reduce their blood pressure so it is in the healthy range. [infokid.org.uk]

  Nevertheless, a low nephron number is described in deceased patients with hypertension [ 16 ]. [dx.doi.org]

• Low Set Ears

  Because the amniotic fluid normally acts as a cushion, too little fluid can cause compression of the fetus resulting in further malformations and problems such as growth retardation; pulmonary hypoplasia (underdeveloped lungs); low-set ears; and a broad [birthdefects.org]

  Regarding the clinical presentation, patients exhibit the Potter sequence, which is characterized by extrarenal features such as wide-set eyes, epicanthal folds, flat nose, large low-set ears with absent cartilage, receding chin, and limb defects. [symptoma.com]

  Oligohydramnios, low birth weight Potter facies: curved skin fold below the eye, low-set ears, dry wrinkled skin. [urology-textbook.com]

  Potter's facies include a square "parrot-beaked" nose, hypomandibulosis, epicanthic folds, a rounded head, wide set eyes, and low set ears. Visualisation of other defects may be hampered by the squashed position of fetus. [perinatal.nhs.uk]

  Babies with bilateral renal agenesis will have a number of unique characteristics: dry loose skin, wide-set eyes, prominent folds at the inner corner of each eye, sharp nose, and large low-set ears with lack of ear cartilage. [health.state.mn.us]

• Irritability

  We present a 43-year-old married man who suffered from difficulty in urination and irritating voiding symptoms for 3 years. The symptoms worsened in the last 6 months. [ncbi.nlm.nih.gov]

  Babies and children with UTIs may become irritable, have a fever, have pain on weeing, feel sick or be sick. If your child has a UTI, he or she will need to take antibiotics, medicines that kill the germs. [infokid.org.uk]

• Hematuria

  She had first noticed hematuria when she was 17 years old. She had never menstruated and had noticed an abnormality in her genitals. The hematuria has been cyclical since the first episode, the last one being 3 weeks prior to presentation. [hoajonline.com]

  チャンス血尿（Asymptomatic hematuria　無症候性血尿） chance proteinuriaチャンス蛋白尿 chancroid軟性下疳 Chlamydia infectionクラミジア感染症 chronic glomerulonephritis (CGN)慢性糸球体腎炎 chronic kidney disease （CKD）慢性腎疾患 chronic nephritic syndrome慢性腎炎症候群 chronic renal failure （CRF）慢性腎不全 colicky [tokyo-med.ac.jp]

  He was completely asymptomatic, although he experienced gross hematuria 10 months before his visit. [ci.nii.ac.jp]

  The first case was a 43-year-old male, with chief complaint of hematuria with blood clot. After laboratory and urological examinations, right nephrectomy was performed for suspicious ureteral tumor. [webview.isho.jp]

  Others include dysuria, urinary frequency, hematuria, urinary tract infections, infertility, hemospermia and, rarely, enuresis. [appliedradiology.com]

• Renal Injury

  Google Scholar 4 : Are pediatric patients more susceptible to major renal injury from blunt trauma? A comparative study. J Urol 1998 ; 160 : 138. Google Scholar 5 : Blunt renal trauma in childhood. Features indicating severe injury. [doi.org]

  Renal hypertrophy was identified in 89 (43%) cases. Children with renal injury had renal hypertrophy in 38% of cases, whereas children without renal injury had renal hypertrophy in 45% of cases (P = NS). [dx.doi.org]

• Anuria

  Leg deformity (excessive flexion of hip and knees) Respiratory insufficiency Anuria and increasing retention parameters Diagnosis of Potter's Syndrome Maternal ultrasound screening: oligohydramnios and no kidney tissue visible. [urology-textbook.com]

  The baby presents with Potter sequence, characterized by anuria, oligohydram-nios (decreased volume of amniotic fluid), and hypoplastic lungs secondary to the oligohydramnios. [78stepshealth.us]

  アデノーマ adrenal tumor副腎腫瘍 adrenogenital syndrome副腎性器症候群 afferent arteriole輸入細動脈 albuminuriaアルブミン尿 alkalemiaアルカリ血症 alkalosisアルカローシス alpha-blockerα-ブロッカー anasarca全身性浮腫 androgen excess男性ホルモン過剰 andrological男性［病］学の angiomyolipoma血管筋脂肪腫 antihypertensive drug降圧薬 anuria [tokyo-med.ac.jp]

Routine widespread use of prenatal ultrasonography improves detection of renal agenesis and other conditions associated with it. Findings are likely to include oligohydramnios, absent kidney(s), absent bladder (particularly in bilateral renal agenesis), hypertrophy of the solitary kidney secondary to compensation (in a fetus with unilateral renal agenesis), and other abnormalities. Moreover, color doppler ultrasonography demonstrates the presence of the renal artery(ies) [10]. The presence of an ectopic kidney should be considered and ruled out [11].

Prenatal magnetic resonance imaging (MRI) may be useful for confirmation of bilateral renal agenesis when ultrasonography is not definitive [12].

A special procedure known as amnioinfusion can be used to evaluate low levels of amniotic fluid [13].

Postnatal tests

Neonatal laboratory studies include serum electrolyte measurements, renal function tests, complete blood count (CBC), and urinalysis. Additionally, levels of urine sodium, creatinine,and osmolality may be warranted.

Various imaging modalities such as abdominal ultrasonography, MRI, and computed tomography (CT) can be performed on the neonate to confirm the congenital defects identified prenatally. Procedures such as voiding cystourethrography and nuclear renal scanning are used to evaluate the genitourinary tract. Additionally, a chest x-ray is used to assess pulmonary hypoplasia.

Genetic tests

All pregnant women carrying fetus(es) with congenital defects should undergo genetic counseling and possibly testing. The family history is a significant component of the workup.

Very importantly, chromosomal analysis for various trisomies and conditions are indicated in infants with a clinical picture suggestive of a genetic disorder [1].

• Small Kidney

  MATERIAL AND METHODS: In this single center, cross-sectional study, a total of 55 patients (39 (% 70.9) with unilateral small kidney and 16 (%29.1) with renal agenesis) were included. The median age was 35 (21-50) years. [ncbi.nlm.nih.gov]

  […] down adrenal (arrow) It is important to differentiate between renal agenesis and a small atrophic kidney, if possible. [fetalsono.com]

  kidney, nonfunctioning kidney, pelvic kidney, renal anomaly, single kidney congenital (left, right, or not specified), and unilateral small kidney. [nature.com]

• Unilateral Small Kidney

  MATERIAL AND METHODS: In this single center, cross-sectional study, a total of 55 patients (39 (% 70.9) with unilateral small kidney and 16 (%29.1) with renal agenesis) were included. The median age was 35 (21-50) years. [ncbi.nlm.nih.gov]

  kidney, nonfunctioning kidney, pelvic kidney, renal anomaly, single kidney congenital (left, right, or not specified), and unilateral small kidney. [nature.com]

This condition should be considered to prevent misdiagnosis or suboptimal treatment. [ncbi.nlm.nih.gov]

“It’s only an appropriate treatment for fetuses with no kidneys, or for those with non-functioning kidneys, who don’t have other genetic or serious anomalies. We are not currently looking at this treatment for low fluid of other etiologies.” [hopkinsmedicine.org]

Dialysis is a treatment that filters and purifies the blood using a machine. This helps keep your body in balance when the kidneys can’t do their job. Factors such as lung development and overall health determine the success of this treatment. [healthline.com]

Prognosis of patients with unilateral renal agenesis. [mayoclinic.pure.elsevier.com]

Argueso LR, Ritchey ML, Boyle ET Jr, Milliner DS, Bergstralh EJ, Kramer SA (1992) Prognosis of children with solitary kidney after unilateral nephrectomy. J Urol (in press) Google Scholar 12. [link.springer.com]

The prognosis of individuals with isolated URA is good. There are reports of hypertension and renal insufficiency in long-term studies of patients with a single kidney, and lifetime follow-up is recommended. [ncbi.nlm.nih.gov]

What is the Prognosis of Bilateral Renal Agenesis? (Outcomes/Resolutions) The prognosis of Bilateral Renal Agenesis is very poor; neonatal deaths are unavoidable. [dovemed.com]

Prognosis In the absence of kidney injury or disease, the prognosis for unilateral renal agenesis is excellent. Individuals with unilateral renal agenesis usually lead normal, healthy lives. [encyclopedia.com]

Renal agenesis is a rare condition of unknown etiology frequently seen together with ipsilateral seminal vesicle and vas deferens anomalies because of common embryologic development. [ncbi.nlm.nih.gov]

The etiology of renal agenesis is suggested. In many instances there are anomalies of other parts of the body. In a few cases it is recognized that genetic factors are responsible. [pediatrics.aappublications.org]

Etiology of Potter's Syndrome: Recessive inheritance is likely, siblings of children with bilateral renal agenesis are also affected in 3.5%. [urology-textbook.com]

( 11454140, 10777380 ) Di george syndrome focal and segmental glomeruosclerosis association of cystic adenomatoid malformation (CCAM type 2 or CPAM) and left heart hypoplasia penile agenesis cat eye syndrome (partial terasomy 22) 47,XXX ( 2669483 ) Etiology [humpath.com]

Epidemiology of Potter's syndrome: Incidence: 3–15/100.000 births for bilateral renal agenesis, 3–20/100.000 births for bilateral renal dysgenesia. In 75%, boys are affected. [urology-textbook.com]

[…] kidney、renal dysplasia）」「腎低形成（hypoplastic kidney、renal hypoplasia）」「腎無形成（renal agenesis）」「逆流性腎症（reflux nephropathy）」「水腎症（hydronephrosis）」「膀胱尿管逆流（vesicoureteric reflux）」「腎盂尿管移行部狭窄（pelviureteric junction obstruction）」「後部尿道弁（posterior urethral valves）」「疫学（epidemiology [natureasia.com]

Echandía, Associate Professor, Department of Pediatrics, Faculty of Health, Universidad del Valle, Master�s in Epidemiology, for his collaboration in the initial protocol and questionnaire. [colombiamedica.univalle.edu.co]

This article reviews the embryology, epidemiology, etiology, clinical features and other malformations associated with congenital renal agenesis. [sjkdt.org]

Clinical-epidemiological analysis of a large consecutive series of malformates infants. Am J Med Genet A. 2008;1;146:15-25. 8. Granese R, Coco C, Jeanty P. [tmj.ro]

[…] at birth Lack of amniotic fluid (oligohydramnios) with BRA, causing complications such as impaired fetal lung development, thoracic compression, limb contractures, and other abnormalities BRA is always fatal Formerly called Potter's syndrome Overview-Pathophysiology [quizlet.com]

Pathophysiology Prior to 16 weeks' gestations, the amount of amniotic fluid is dependent on the transmembrane flow. After that, fetal urine production is the predominant mechanism that determines the amniotic fluid volume. [emedicine.medscape.com]

The pathophysiological mechanisms leading to total absence of kidney development thus remain largely elusive. [ncbi.nlm.nih.gov]

Unilateral renal agenesis cases complicated by associated such anomalies need definitive management and lifelong clinical monitoring to diagnose and prevent chronic kidney disease. [ncbi.nlm.nih.gov]

Case: We report a case of renal agenesis identified in a fetus in which serial amnioinfusions were employed to prevent pulmonary hypoplasia and compression effects. A total of ten amnioinfusions were performed between 17-33 weeks' gestation. [journals.lww.com]

1. Sanna-Cherchi S, Caridi G, Weng PL, et al. Genetic approaches to human renal agenesis/hypoplasia and dysplasia. Pediatr Nephrol. 2007; 22(10):1675-1684.
2. Robson WL, Leung AK, Rogers RC. Unilateral renal agenesis. Adv Pediatr. 1995;42:575-92.
3. Woolf AS, Hillman KA. Unilateral renal agenesis and the congenital solitary functioning kidney: developmental, genetic and clinical perspectives. BJU Int. 2007; 99(1):17–21.
4. Atiyeh B, Husmann D, Baum M. Contralateral renal abnormalities in patients with renal agenesis and noncystic renal dysplasia. Pediatrics. 1993;91(4):812–815.
5. Khatemi F. Potter's Syndrome: A Study of 15 patients. Arch Iranian Med, 2004; 7(3):186-9.
6. Potter E. Bilateral renal agenesis. J Pediatr. 1946;26:68–76.
7. Potter E. Bilateral absence of ureter and kidney. Obstetrics and Gynecology. 1965; 25: 3-12.
8. Greenwood RD, Rosenthal A, Nadas AS. Cardiovascular malformations associated with congenital anomalies of the urinary system. Observations in a series of 453 infants and children with urinary system malformations. Clin Pediatr (Phila). 1976; 15(12):1101-4.
9. Jain M, Agarwal S, Mandal S. Variation in clinical and genitourinary lesions associated with pulmonary hypoplasia in Potter's syndrome--two autopsy reports. Indian J Pathol Microbiol. 2006;49(3):416-8.
10. Sepulveda W, Stagiannis KD, Flack NJ, Fisk NM. Accuracy of prenatal diagnosis of renal agenesis with color flow imaging in severe second-trimester oligohydramnios. Am J Obstet Gynecol. 1995; 173(6):1788-92.
11. Uematsu M, Sakamoto O, Nishio T, et al. A case surviving for over a year of renal tubular dysgenesis with compound heterozygous angiotensinogen gene mutations. Am J Med Genet A. 2006; 140(21):2355-60.
12. Gęca T, Krzyżanowski A, Stupak A, et al. Complementary role of magnetic resonance imaging after ultrasound examination in assessing fetal renal agenesis: a case report. J Med Case Rep. 2014;8(1):96.
13. Fisk NM, Ronderos-Dumit D, Soliani A, et al. Diagnostic and therapeutic transabdominal amnioinfusion in oligohydramnios. Obstet Gynecol. 1991; 78(2):270-8.