Home | About Us | Editorial Board | Current Issue | Archives | Search | Instructions | Subscription | Feedback | e-Alerts | Login 
Journal of Indian Society of Pedodontics and Preventive Dentistry Official publication of Indian Society of Pedodontics and Preventive Dentistry
 Users Online: 793  
  Print this page Email this page   Small font sizeDefault font sizeIncrease font size

  Table of Contents    
Year : 2012  |  Volume : 30  |  Issue : 2  |  Page : 169-172

Enamel renal syndrome: A rare case report

1 Department of Orthodontics and Dentofacial Orthopedics, C. K. S. Teja Institutions of Dental Sciences, Tirupati, Andhra Pradesh, India
2 Department of Pedodontics, C. K. S. Teja Institutions of Dental Sciences, Tirupati, Andhra Pradesh, India
3 Department of Oral Medicine and Radiology, C. K. S. Teja Institutions of Dental Sciences, Tirupati, Andhra Pradesh, India

Date of Web Publication23-Aug-2012

Correspondence Address:
S V Kala Vani
Department, of Orthodontics and Dentofacial Orthopedics, C. K. S. Teja Institutions of Dental Sciences, Tirupati,Andhra Pradesh
Login to access the Email id

Source of Support: None, Conflict of Interest: None

DOI: 10.4103/0970-4388.100006

Rights and Permissions



Enamel renal syndrome is a very rare disorder associating amelogenesis imperfecta with nephrocalcinosis. It is known by various synonyms such as amelogenesis imperfecta nephrocalcinosis syndrome, MacGibbon syndrome, Lubinsky syndrome, and Lubinsky-MacGibbon syndrome. It is characterized by enamel agenesis and medullary nephrocalcinosis. This paper describes enamel renal syndrome in a female patient born in a consanguineous family.

Keywords: Amelogenesis imperfecta, delayed eruption, enamel renal syndrome, nephrocalcinosis; renal ultrasound

How to cite this article:
Kala Vani S V, Varsha M, Sankar Y U. Enamel renal syndrome: A rare case report. J Indian Soc Pedod Prev Dent 2012;30:169-72

How to cite this URL:
Kala Vani S V, Varsha M, Sankar Y U. Enamel renal syndrome: A rare case report. J Indian Soc Pedod Prev Dent [serial online] 2012 [cited 2022 May 29];30:169-72. Available from: https://www.jisppd.com/text.asp?2012/30/2/169/100006

   Introduction Top

Enamel-renal syndrome (ERS, OMIM 204690) is characterized by hypoplastic amelogenesis imperfecta (AI) and nephrocalcinosis (NC). It is listed as a "rare disease" by the office of rare diseases (ORD) of the National Institutes of Health (NIH). This means ERS affects less than 200,000 people in the US population. The common features of this syndrome are the presence of thin or no enamel, delayed tooth eruption, intrapulpal calcifications, bilateral nephrocalcinosis, and normal plasma calcium.

Amelogenesis imperfecta is a heterogeneous group of conditions, genomic in origin, which affects the structure and clinical appearance of the enamel of all or nearly all the teeth in a more or less equal manner and which may be associated with morphologic or biochemical changes elsewhere in the body. [1] It occurs with a frequency of 1 : 700 [2] to 1 : 14000 [3] as an isolated defect. It shows autosomal dominant, autosomal recessive, x-Linked and sporadic inheritance patterns. The enamel may be hypoplastic, hypomineralized, or hypomature, depending on the clinical presentation of the defects and the likely stage of enamel formation that is primarily affected.

Although AI is generally considered to primarily affect the dental enamel, other oral and dental stigmata including delayed tooth eruption, unerupted teeth, anterior open bite, pulpal calcifications, inter-radicular dentinal dysplasia, intracoronal resorption, taurodontism have been shown to co-exist. [4],[5] In addition, it is a feature of several multiorgan syndrome but pathognomonic of only a few. [2],[4],[6],[7]

In the past 30 years, an extremely rare syndrome associating AI with NC has been reported in just a few families. [4],[6],[7],[8],[9],[10],[11],[12],[13],[14] Nephrocalcinosis is a common disease characterized by the precipitation of calcium salts in the renal tissue. In the patients with ERS, the impaired renal function is variable or delayed to adulthood despite the presence of typical renal hyperechogenicity in childhood. The relation between the enamel defect and NC is still unknown.

   Case Report Top

A 11-year-old female patient presented with failure of eruption of upper and lower permanent teeth. Apart from the consanguineous marriage, her parents had past dental and medical history was noncontributory. There was no family history of either AI or failure of eruption of permanent teeth and her elder male sibling showed normal dental development. Her general, physical, and clinical findings were normal.

On intraoral examination, it was found that all deciduous teeth were retained and exhibited advanced wear, the molars being devoid of any cuspal features. The permanent mandibular first molars have erupted and permanent maxillary first molars are erupting. The retained deciduous teeth and permanent first molars showed yellow discoloration. Severe attrition resulted in anterior open bite [Figure 1].
Figure 1: Intraoral photographs showing enamel discoloration, marked attrition, and anterior openbite. (a) Frontal view, (b) right lateral view,(c) left lateral view, (d) maxillary occlusal view, (e) mandibular occlusal view

Click here to view

The panoramic radiograph [Figure 2] showed all permanent teeth including third molars. All the permanent teeth showed delayed eruption. The contrast between enamel and dentine was reduced indicating low mineral content of enamel. Intrapulpal calcifications were limited to some primary and permanent teeth.
Figure 2: Orthopantomogram revealing multiple unerupted permanent teeth with lack of contrast between enamel and dentine and intracoronal pulp calcifications in deciduous and unerupted permanent teeth. Black arrows indicating intracoronal pulp calcifications

Click here to view

The ultrasound examination of her kidneys and bladder [Figure 3] demonstrated multiple hyperechoic foci with posterior acoustic shadowing in all the medulla in both kidneys suggestive of bilateral nephrocalcinosis. The size of the kidneys was normal and there were no urinary tract abnormalities. No other relevant renal history was present.
Figure 3: Renal ultrasound showing bilateral nephrocalcinosis

Click here to view

The serum biochemical markers and hematological parameters were all in the normal range. No abnormalities were detected in her endocrinal profile, which would exclude the involvement of metabolic hard tissue disease. Her renal function tests showed normal blood urea (3.82 mmol /L), normal serum creatinine (61.88 μmol/L), normal creatinine clearance (1.90 mL/s), normal serum electrolytes (Na: 140 mmol/L, K: 4.9 mmol/L, Cl: 105 mmol/L), and normal blood gas findings (HCO3 --- : 22 mmol/L). Twenty-four-hour urinalysis revealed normal urine creatinine (6.0 mmol/ day), normal protein (0.064 g/ day), hypocalciuria (0.575 mmol/ day; normal: 1.25-6.25 mmol/day) and low urine phosphate levels (1.0 mmol/day; normal: 15-50 mmol/day). Fractional excretion of calcium also has reduced (0.8%; normal: 1%).

   Discussion Top

The syndrome of ERS has been previously described in 15 cases [4],[6],[7],[8],[9],[10],[11],[12],[13],[14] from consanguineous as well as nonconsanguineous families. All cases had thin or absent enamel and bilateral NC. While some cases progressed to renal insufficiency, [8],[9],[10],[11],[13] others featured certain renal tubular disorders. [4],[6],[9],[11],[13] Some cases reported association of this syndrome with other renal disorders such as polycystic kidney disease and distal renal tubular acidosis. [6]

In the present case, NC was detected after the clinical and radiological diagnosis of AI. Nephrocalcinosis may remain undetected until patients present with recurrent urinary tract infections, pyelonephritis, or passage of a stone. In these conditions, the ultrasound appearance of NC are indistinguishable from other causes of medullary NC. In the course of preparation of this case for paper presentation, we conducted an electronic literature search on the keywords AI and delayed eruption. This revealed an extremely rare association of AI with NC. As a precautionary measure, she was referred to a radiologist for ultrasound examination of kidneys and bladder that revealed bilateral medullary NC. The consanguineous marriage of the patient's parents suggests an autosomal recessive inheritance in this condition. Out of different forms of AI, hypoplastic type is frequently associated with this syndrome. [6] Kirzioglu et al. [5] analyzed the prevalence of NC in AI patients by renal ultrasound, revealing suspicious radiopacities in one out of five patients with a diagnosis of AI. Interestingly, all patients with evidence of NC were classified as the hypoplastic type of AI.

Delayed tooth eruption exhibited by this patient was in its most severe form with only permanent mandibular first molars erupted unlike other cases reported on ERS. [4],[6],[7],[9],[11],[12],[14] Seow [15] reported that tendency towards delayed eruption in AI patients was six times that of unaffected individuals and the most severe cases occurring in autosomal recessive hypoplastic AI. [16] Earlier studies suggested that delay of eruption could be due to pathology of dental follicle. [11],[17],[18]

Intrapulpal calcifications as revealed by panoramic film of this patient is frequently exhibited by autosomal recessive hypoplastic AI. Cosegregation of delayed tooth eruption, pulp calcification, and hypoplastic enamel has been first reported by Peters et al.[16] and strongly suggests that the mutation causing this AI type involves a gene expressed in ameloblasts as well as in other odontogenic tissues. The association of ERS with this triad has been reported previously. [4],[7],[9],[10],[12],[14] Gingival enlargement and intracoronal resorption have also been reported [4],[7],[10],[11],[12],[14] but were not seen in this case.

Concerning the renal pathology, NC remains unexplained. In ERS syndrome, no predisposing factors such as hypercalcemia, hypercalciuria have been found. On the contrary hypocalciuria, [9],[10],[11] low phosphate in urine [9],[11] and proteinuria [4],[10] have been reported . Our patient also has low urinary calcium and phosphate with normal urinary proteins. It remains unclear whether these are the cause or consequence of this syndrome or whether it may be involved in the nephrocalcinosis. Cases so far reported, suggest that there is no abnormality of bone metabolism.

Histologically detectable NC has been reported as an incidental finding in upto 100% of autopsies. Radiographically detectable NC is much less common. [19] This syndrome therefore seems to combine one uncommon condition (AI) with one much less common (NC). Although rare syndrome untreated NC is known to be associated with significant morbidity.

Paradigms behind the etiopathogenesis of ERS include pleotrophism, [7] abnormality in interstitial matrix leading to dystrophic calcification, [9] expression of tissue specific dental proteins in dental and nondental tissues, [6],[10] and symbiotic role of albumin and osteopontin. [10],[11] Significant progress has to be made to define the genetic defect behind ERS and further research is needed to clarify the pathogenesis of AI and NC.

Though, often asymptomatic NC can be associated or can lead to the impaired renal function. It is mandatory to alert the dentists who see children with generalized hypoplastic AI, should obtain a detailed family history and past medical history with particular reference to urinary tract and should be referred for medical examination including renal function tests and ultrasonography to detect NC. Similarly, awareness must be created among nephrologists to recommend oral examination in children with unexplained NC associated with unusual appearance of teeth.

   References Top

1.Aldred MJ, Crawford PJ, Savariraya R. Amelogenesis Imperfecta - A classification and catalogue for the 21st century. Oral Dis 2003;9:19-23.  Back to cited text no. 1
2.Backman B, Holm AK. Amelogenesis imperfecta: Prevalence and incidence in a northern Swedish county. Community Dent Oral Epidemol 1986;14:43-7.  Back to cited text no. 2
3.Witkop CJ, Sauk JJ. Heritable defects of enamel. In: Stewart RE, Prescott GH, editors. Oral facial genetics. St. Louis: C.V Mosby; 1976. p. 151-226.  Back to cited text no. 3
4.Hunter L, Addy LD, Knox J, Drage N. Is amelogenesis imperfecta an indication for renal examination? Int J Paediatric Dent 2007;17:62-5.  Back to cited text no. 4
5.Kirizioglu Z, Ulu KG, Sezer MT, Yuksel S. The relationship of amelogenesis imperfecta and nephrocalcinosis syndrome. Med Oral Patol Oral Cir Bucal 2009;14:e579-82.  Back to cited text no. 5
6.Elizabeth J, Lakshmi Priya E, Umadevi KM, Ranganathan K. Amelogenesis imperfecta with renal disease - A report of two cases. J Oral Pathol Med 2007;36:625-8.  Back to cited text no. 6
7.Hall RK, Phakey P, Palamara J, McCredie DA. Amelogenesis imperfecta and nephrocalcinosis syndrome. Case studies of clinical features and ultrastructure of tooth enamel in two siblings. Oral Surg Oral Med Oral Pathol Oral Radiol Endod 1995;79:583-92.  Back to cited text no. 7
8.MacGibbon D. Generalized enamel hypoplasia and renal dysfunction. Aust Dent J 1972;17:61-3.  Back to cited text no. 8
9.Lubinsky M, Angle C, Marsh PW, Witkop CJ Jr. Syndrome of amelogenesis imperfecta, nephrocalcinosis, impaired renal concentration and possible abnormality of calcium metabolism. Am J Med Genet 1985;20:233-43.  Back to cited text no. 9
10.Dellow EL, Harley KE, Unwin RJ, Wrong O, Winter GB, Parkins BJ. Amelogenesis imperfecta, nephrocalcinosis and hypocalciuria syndrome in two siblings from a large family with consanguineous parents. Nephrol Dial Transplant 1998;13:3193- 6.  Back to cited text no. 10
11.Normand de la Tranchade I, Bonarek H, Marteau JM, Boileau MJ, Nancy J. Amelogenesis imperfecta and nephrocalcinosis: A new case of this rare syndrome. J Clin Pediatr Dent 2002;27:171- 6.  Back to cited text no. 11
12.Paula LM, Melo NS, Silva Guerra EN, Mestrinho DH, Acevedo AC. Case report of a rare syndrome associating amelogenesis imperfecta and nephrocalcinosis in a consanguineous family. Arch Oral Biol 2005;50:237-42.  Back to cited text no. 12
13.Fu XJ, Nozu K, Goji K, Ikeda K, Kamioka I, Fujita T, et al. Enamel-renal syndrome associated with hypokalaemic metabolic alkalosis and impaired renal concentration: A novel syndrome? Nephrol Dial Transplant 2006;21:2959-62.  Back to cited text no. 13
14.Martelli-Junior H, Santos Neto PE, de Aquino SN, de Oliveira Santos CC, Borges SP, Oliveira EA, et al. Amelogenesis imperfecta and nephrocalcinosis syndrome: A case report and review of literature. Nephron Physiol 2011;118:62-5.  Back to cited text no. 14
15.Seow WK. Dental development in amelogenesis imperfecta: A controlled study. Pediatr Dent 1995;17:26-30.  Back to cited text no. 15
16.Peters E, Cohen M, Altini M. Rough hypoplastic amelogenesis imperfecta with follicular hyperplasia. Oral Surg Oral Med Oral Pathol 1992;74:87-92.  Back to cited text no. 16
17.Marks SC Jr. The basic and applied biology of tooth eruption. Connect Tissue Res 1995;32:149-57.  Back to cited text no. 17
18.Wise GE. Cells and molecular bio of tooth eruption. In: Davidovitch Z, editor. The biological mechanisms of tooth eruption, resorption and replacement by implants, Birmingham, AL: EBSCO Media; 1998.  Back to cited text no. 18
19.Wrong O. Nephrocalcinosis. In: Davison AM, Cameron JS, Grunfeld J, Kerr DNS, Ritz E, Winearls CG, editors. Oxford text book of clinical nephrology. 2nd ed. Oxford: Oxford University Press; 1998. p. 1375-96.  Back to cited text no. 19


  [Figure 1], [Figure 2], [Figure 3]

This article has been cited by
1 Enamel renal syndrome: A systematic review
MariaLuiza Morais Farias, GabrielaOliveira Ornela, RodrigoSoares de Andrade, DaniellaReis B. Martelli, VerônicaOliveira Dias, HercílioMartelli Júnior
Indian Journal of Nephrology. 2021; 31(1): 1
[Pubmed] | [DOI]
2 Enamel Renal Syndrome: A Case Report of Amelogenesis Imperfecta Associated with Nephrocalcinosis
Sooji Choi, Young Bae Sohn, Suk Ji, Seungil Song, Jeongwon Shin, Seunghye Kim
[Pubmed] | [DOI]
3 Two new families with enamel renal syndrome: A novel FAM20A gene mutation and review of literature
Nehal F. Hassib, Mona A. Shoeib, Hoda A. ElSadek, Mona E. Wali, Mostafa I. Mostafa, Mohamed S. Abdel-Hamid
European Journal of Medical Genetics. 2020; 63(11): 104045
[Pubmed] | [DOI]
4 Enamel-renal-gingival syndrome andFAM20Amutations
Piranit Nik Kantaputra,Massupa Kaewgahya,Udomrat Khemaleelakul,Prapai Dejkhamron,Suchitra Sutthimethakorn,Visith Thongboonkerd,Anak Iamaroon
American Journal of Medical Genetics Part A. 2013; : n/a
[Pubmed] | [DOI]


Print this article  Email this article


    Similar in PUBMED
   Search Pubmed for
   Search in Google Scholar for
 Related articles
    Article in PDF (1,023 KB)
    Citation Manager
    Access Statistics
    Reader Comments
    Email Alert *
    Add to My List *
* Registration required (free)  

   Case Report
    Article Figures

 Article Access Statistics
    PDF Downloaded441    
    Comments [Add]    
    Cited by others 4    

Recommend this journal

Contact us | Sitemap | Advertise | What's New | Copyright and Disclaimer | Privacy Notice
 © 2005 - Journal of Indian Society of Pedodontics and Preventive Dentistry | Published by Wolters Kluwer - Medknow 
Online since 1st May '05