Balkan Journal of Medical Genetics

CHARACTERISTIC DIAGNOSTIC CLUES OF METATROPIC DYSPLASIA: THE LUMBOTHORACIC HUMPBACK WITH DUMBBELL APPEARANCE OF THE LONG BONES
Gucev Z, Kalcev G, Laban N, Bozinovski Z, Popovski N, Saveski A, Daskalov B, Plaseska-Karanfilska D, Tasic V
*Corresponding Author: Professor Zoran Gucev, Department for Endocrinology and Genetics, University Children’s Hospital, Medical Faculty Skopje, Majka Teresa BB, Skopje 1000, Republic of Macedonia. Tel.: +389-70-279-742. Fax: +389-3-226-356. E-mail: gucevz@gmail.com
page: 35

DISCUSSION

The clinical diagnosis of a bone dysplasia can be rather complex. There are not only many overlapping skeletal dysplasias, but there are complex and overlapping phenotypes in the frame of one disease. There are three types of MD: 1) a nonlethal autosomal recessive form; 2) a nonlethal dominant form, and 3) a lethal form with possible autosomal recessive inheritance. However, the distinction between these three types has proven to be difficult. Typically, the radiological manifestations of dumbbell aspect of the long bones, severe platyspondyly and severe scoliosis, are pointing towards the nonlethal autosomal recessive form of MD [1,6]. Nevertheless, some researchers have found a striking evolution of the skeletal anomalies with amelioration of the size of the long bones and significant improvement of the platyspondyly resulting in almost normal vertebral bodies at 15 years of age, was also reported [1]. On the contrary, Dai et al. [7] found that the evolution of body proportion with age was not essential, while only the prominent joints were consistently found in MD. Andreucci et al. [2] suggested that the TRPV4 skeletal dysplasias have a phenotypic overlap, even within the same family. To add to the complexity of the phenotype, a likely somatic mosaicism in an L618P patient with mild-er clinical presentation. Therefore, no definite genotype-phenotype correlation could be observed. The degree of activation of the TRPV4 gene was thought to predict the severity of the phenotype. Our patient had the knock-knees as a prominent feature. This feature was not an effect of rickets, as the laboratory investigation and X-rays have proven. This was not found in the other Figure 3. The c.2396C>T; p.Pro799Leu (P799L) mutation in the TPRV4 gene. skeletal peculiarities reported as precocious calcification of hyoid and cricoid cartilage, severe hypoplasia of the anterior portion of the first cervical vertebrae, irregular and squared-off calcaneal bones, and microcalcifications in vertebral bodies and epiphyses [1]. In this report the leading sign pointing to the diagnosis of MD in our patient was the humpback (the gibbous) in the upper lumbar and lower thoracic vertebrae. Fortunately, our patient did not have any of the described complications that can jeopardize the patient’s life. Laryngotracheal dysfunction can compromise aspiration, while the thoracic kyphoscoliosis can progress rapidly and can be out of surgical manageability. The short stature can be in the range of dwarfism 107-135cm. Cervical instability, hearing loss, degenerative joint deformity can add to the misery of the patients [6]. Our patient’s gibbous was not surgically corrected, so far, braces have been used. Conclusions. This is the first patient with MD in the Republic of Macedonia. Knock-knees were the cause of his referral, as a peculiarity of his phenotype. The very presence of the humpback and the dumbbell appearance of the long bones distinguished the MD from other bone dysplasias with similar characteristics. We believe that the presence of those two features can shorten the path to accurate diagnosis in the crowded field of overlapping skeletal dys-plasias. The diagnosis of MD in this patient was further confirmed by the discovery of the mutation c.2396C>T [p.Pro799Leu (P799L)] of the TRPV4 gene. Declaration of Interest. The authors report no conflicts of interest. The authors alone are responsible for the content and writing of this article.

Number 27 VOL. 27 (2), 2024	Number 27 VOL. 27 (1), 2024
Number 26 Number 26 VOL. 26(2), 2023 All in one	Number 26 VOL. 26(2), 2023
Number 26 VOL. 26, 2023 Supplement	Number 26 VOL. 26(1), 2023
Number 25 VOL. 25(2), 2022	Number 25 VOL. 25 (1), 2022
Number 24 VOL. 24(2), 2021	Number 24 VOL. 24(1), 2021
Number 23 VOL. 23(2), 2020	Number 22 VOL. 22(2), 2019
Number 22 VOL. 22(1), 2019	Number 22 VOL. 22, 2019 Supplement
Number 21 VOL. 21(2), 2018	Number 21 VOL. 21 (1), 2018
Number 21 VOL. 21, 2018 Supplement	Number 20 VOL. 20 (2), 2017
Number 20 VOL. 20 (1), 2017	Number 19 VOL. 19 (2), 2016
Number 19 VOL. 19 (1), 2016	Number 18 VOL. 18 (2), 2015
Number 18 VOL. 18 (1), 2015	Number 17 VOL. 17 (2), 2014
Number 17 VOL. 17 (1), 2014	Number 16 VOL. 16 (2), 2013
Number 16 VOL. 16 (1), 2013	Number 15 VOL. 15 (2), 2012
Number 15 VOL. 15, 2012 Supplement	Number 15 Vol. 15 (1), 2012
Number 14 14 - Vol. 14 (2), 2011	Number 14 The 9th Balkan Congress of Medical Genetics
Number 14 14 - Vol. 14 (1), 2011	Number 13 Vol. 13 (2), 2010
Number 13 Vol.13 (1), 2010	Number 12 Vol.12 (2), 2009
Number 12 Vol.12 (1), 2009	Number 11 Vol.11 (2),2008
Number 11 Vol.11 (1),2008	Number 10 Vol.10 (2), 2007
Number 10 10 (1),2007	Number 9 1&2, 2006
Number 9 3&4, 2006	Number 8 1&2, 2005
Number 8 3&4, 2004	Number 7 1&2, 2004
Number 6 3&4, 2003	Number 6 1&2, 2003
Number 5 3&4, 2002	Number 5 1&2, 2002
Number 4 Vol.3 (4), 2000	Number 4 Vol.2 (4), 1999
Number 4 Vol.1 (4), 1998	Number 4 3&4, 2001
Number 4 1&2, 2001	Number 3 Vol.3 (3), 2000
Number 3 Vol.2 (3), 1999	Number 3 Vol.1 (3), 1998
Number 2 Vol.3(2), 2000	Number 2 Vol.1 (2), 1998
Number 2 Vol.2 (2), 1999	Number 1 Vol.3 (1), 2000
Number 1 Vol.2 (1), 1999	Number 1 Vol.1 (1), 1998

About the journal ::: Editorial ::: Subscription ::: Information for authors ::: Contact