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Segmental multicystic dysplastic kidney: A rare situation
Journal of Pediatric Urology (2011) 7, 491e494
CASE REPORT
Segmental multicystic dysplastic kidney: A rare situation Alexandre Iscaife, Mauro Barbosa, Valdemar Ortiz, Antonio Macedo Jr* Department of Urology, Federal University of Sa˜o Paulo, Rua Maestro Cardim, 560/215, 01323-000 Sa˜o Paulo, Brazil Received 13 July 2010; accepted 3 December 2010 Available online 5 February 2011
KEYWORDS Multicystic dysplastic kidney
Abstract Segmental multicystic dysplastic kidney is a rare subtype, found in only about 4% of children diagnosed with MCDK. To the best of our knowledge, we describe the 36th reported case of segmental multicystic kidney disease. ª 2010 Journal of Pediatric Urology Company. Published by Elsevier Ltd. All rights reserved.
Multicystic dysplastic kidney (MCDK) is a form of renal dysplasia in which there are multiple non-communicating cysts of various sizes separated by dysplastic parenchyma, resulting from abnormal and incomplete kidney development, and renal function is minimal or absent. Segmental MCDK is a rare subtype of this disorder, found in only about 4% of children diagnosed with MCDK. To the best of our knowledge, we describe the 36th case of segmental multicystic kidney disease [1e3].
Case report An 8-year-old female presented after one episode of pyelonephritis and sepsis with a painless, 5-cm palpable mass in the left flank. Ultrasonography revealed the left kidney to be enlarged with multiple cysts affecting only the lower pole, no parenchyma detected, and clear definition of the cyst walls and no communication among them (Fig. 1A
* Corresponding author. Tel./fax: þ55 11 32870639. E-mail address: [email protected] (A. Macedo).
and B). The right kidney was normal. Computerized tomography (CT) showed a multiseptated cystic mass on the lower half of the left kidney which was evident in the non-contrast phase of the exam (Fig. 2A and B). The CT scan in the contrast phase indicated complete absence of function on the lower pole of the left side which was confirmed by DMSA scan (Fig. 3A and B). The DMSA renal scan revealed relative function of 44% in the left and 56% in the right, and the presence of scars could be identified (Fig. 4). Voiding cystourethrography (VCUG) showed bilateral vesicoureteral Grade IVeV reflux (VUR) and left duplex system with a blindended unit up to the mid-ureter correspondent to the dysplastic lower pole (Fig. 5A). A contrast CT scan image is shown which confirms the VCUG findings (Fig. 5B). We performed a common sheath ureteral reimplantation (Cohen) and hemi-nephrectomy of the lower dysplastic pole. The child presented good clinical recovery.
Discussion Segmental multicystic dysplastic kidney (SMDK) occurs either from insufficient interaction of the ureteral bud and
1477-5131/$36 ª 2010 Journal of Pediatric Urology Company. Published by Elsevier Ltd. All rights reserved. doi:10.1016/j.jpurol.2010.12.005
492
A. Iscaife et al.
Figure 1
Ultrasonography reveals multiple cysts affecting only the lower pole of the left kidney.
metanephrons or from prenatal obstruction leading to cystic dysplasia. Cytomegalovirus infection has also been implicated in the development of renal dysplasia [2]. Genetics can also play a role, mainly when there is an association with VUR [4]. Thirty-five SMDK cases have been previously described. Such studies showed that the left kidney and females are mostly affected. These data reinforce the significance of genetics in SMDK development. As for associated
Figure 2
anomalies, the presence of VUR in the contralateral kidney is found in 20e33% of cases. Regarding the ipsilateral kidney, the incidence of associated changes is 77%, lower pole VUR being the most common. These figures reinforce the need to evaluate the entire urinary tract before deciding on treatment [1]. Most of the reported cases were associated with duplex collecting systems. Only 6 of the 35 had a single collecting system [3]. This suggests a similarity between SMDK and
Non-contrast CT scan identifies clearly the cysts on the left lower pole.
Segmental multicystic dysplastic kidney
Figure 3
493
Contrast CT scan (A) and DMSA scan (B) document absence of function of the segmental multicystic dysplastic kidney.
hypodysplasia of a duplex kidney: both have a female predominance, with unilateral involvement occurring on either right or left, and usually located in the upper moiety, which is different to our case. Complete MCDK, on the other hand, has a male predominance and most commonly involves the left kidney. Surgical treatment was indicated in 90% of the cases described. Partial resection seems to be the most appropriate treatment, with the laparoscopic approach most popular today. In our case, the presence of high-grade and bilateral VUR heightened the need for surgical correction, which was carried out using an open intravesical technique. [1] Long-term follow-up data are not available concerning all the patients who underwent surgery. The natural history of SMDK is not well known. Meanwhile, in our patient, based on clinical signs of a life-threatening condition due to sepsis and the risk of kidney failure, surgery was the safest option. When non-surgical treatment is the chosen option because of a lack of symptoms, follow up must be planned for the long term. Figure 4
The split renal DMSA scan.
Figure 5 (A) VCUG shows bilateral Grade IVeV VUR and left duplex system with a blind-ended ureteral unit correspondent to the dysplastic lower pole. (B) Contrast CT-scan image, for comparison.
494
A. Iscaife et al.
Conclusion
References
We have described the 36th case of SMDK, a rare multicystic dysplasia condition presenting with urosepsis. Thus far, surgical treatment seems to be the best indication with special attention to associated abnormalities. Long-term follow up will shed more light upon the natural history of this type of kidney dysplasia.
[1] Kalyoussef E, Hwang J, Rasad V, Barone J. Segmental multicystic dysplastic kidney in children. Urology 2006;68:1121.e9e1121.e11. [2] Eckoldt F, Woderich R, Smith RD, Heling KS. Antenatal diagnostic aspects of unilateral multicystic kidney dysplasia e sensitivity, specificity, predictive values, differential diagnoses, associated malformations and consequences. Fetal Diagn Ther 2004;19:163e9. [3] Lin CC, Tsai JD, Sheu JC, Lu HJ, Chang BP. Segmental multicystic dysplastic kidney in children: clinical presentation, imaging finding, management, and outcome. J Pediatr Surg 2010;45:1856e62. [4] Murer L, Benetti E, Artifoni L. Embryology and genetics of primary vesico-ureteric reflux and associated renal dysplasia. Pediatr Nephrol 2007;22:788e97.
Conflict of interest/funding None.
CASE REPORT
Segmental multicystic dysplastic kidney: A rare situation Alexandre Iscaife, Mauro Barbosa, Valdemar Ortiz, Antonio Macedo Jr* Department of Urology, Federal University of Sa˜o Paulo, Rua Maestro Cardim, 560/215, 01323-000 Sa˜o Paulo, Brazil Received 13 July 2010; accepted 3 December 2010 Available online 5 February 2011
KEYWORDS Multicystic dysplastic kidney
Abstract Segmental multicystic dysplastic kidney is a rare subtype, found in only about 4% of children diagnosed with MCDK. To the best of our knowledge, we describe the 36th reported case of segmental multicystic kidney disease. ª 2010 Journal of Pediatric Urology Company. Published by Elsevier Ltd. All rights reserved.
Multicystic dysplastic kidney (MCDK) is a form of renal dysplasia in which there are multiple non-communicating cysts of various sizes separated by dysplastic parenchyma, resulting from abnormal and incomplete kidney development, and renal function is minimal or absent. Segmental MCDK is a rare subtype of this disorder, found in only about 4% of children diagnosed with MCDK. To the best of our knowledge, we describe the 36th case of segmental multicystic kidney disease [1e3].
Case report An 8-year-old female presented after one episode of pyelonephritis and sepsis with a painless, 5-cm palpable mass in the left flank. Ultrasonography revealed the left kidney to be enlarged with multiple cysts affecting only the lower pole, no parenchyma detected, and clear definition of the cyst walls and no communication among them (Fig. 1A
* Corresponding author. Tel./fax: þ55 11 32870639. E-mail address: [email protected] (A. Macedo).
and B). The right kidney was normal. Computerized tomography (CT) showed a multiseptated cystic mass on the lower half of the left kidney which was evident in the non-contrast phase of the exam (Fig. 2A and B). The CT scan in the contrast phase indicated complete absence of function on the lower pole of the left side which was confirmed by DMSA scan (Fig. 3A and B). The DMSA renal scan revealed relative function of 44% in the left and 56% in the right, and the presence of scars could be identified (Fig. 4). Voiding cystourethrography (VCUG) showed bilateral vesicoureteral Grade IVeV reflux (VUR) and left duplex system with a blindended unit up to the mid-ureter correspondent to the dysplastic lower pole (Fig. 5A). A contrast CT scan image is shown which confirms the VCUG findings (Fig. 5B). We performed a common sheath ureteral reimplantation (Cohen) and hemi-nephrectomy of the lower dysplastic pole. The child presented good clinical recovery.
Discussion Segmental multicystic dysplastic kidney (SMDK) occurs either from insufficient interaction of the ureteral bud and
1477-5131/$36 ª 2010 Journal of Pediatric Urology Company. Published by Elsevier Ltd. All rights reserved. doi:10.1016/j.jpurol.2010.12.005
492
A. Iscaife et al.
Figure 1
Ultrasonography reveals multiple cysts affecting only the lower pole of the left kidney.
metanephrons or from prenatal obstruction leading to cystic dysplasia. Cytomegalovirus infection has also been implicated in the development of renal dysplasia [2]. Genetics can also play a role, mainly when there is an association with VUR [4]. Thirty-five SMDK cases have been previously described. Such studies showed that the left kidney and females are mostly affected. These data reinforce the significance of genetics in SMDK development. As for associated
Figure 2
anomalies, the presence of VUR in the contralateral kidney is found in 20e33% of cases. Regarding the ipsilateral kidney, the incidence of associated changes is 77%, lower pole VUR being the most common. These figures reinforce the need to evaluate the entire urinary tract before deciding on treatment [1]. Most of the reported cases were associated with duplex collecting systems. Only 6 of the 35 had a single collecting system [3]. This suggests a similarity between SMDK and
Non-contrast CT scan identifies clearly the cysts on the left lower pole.
Segmental multicystic dysplastic kidney
Figure 3
493
Contrast CT scan (A) and DMSA scan (B) document absence of function of the segmental multicystic dysplastic kidney.
hypodysplasia of a duplex kidney: both have a female predominance, with unilateral involvement occurring on either right or left, and usually located in the upper moiety, which is different to our case. Complete MCDK, on the other hand, has a male predominance and most commonly involves the left kidney. Surgical treatment was indicated in 90% of the cases described. Partial resection seems to be the most appropriate treatment, with the laparoscopic approach most popular today. In our case, the presence of high-grade and bilateral VUR heightened the need for surgical correction, which was carried out using an open intravesical technique. [1] Long-term follow-up data are not available concerning all the patients who underwent surgery. The natural history of SMDK is not well known. Meanwhile, in our patient, based on clinical signs of a life-threatening condition due to sepsis and the risk of kidney failure, surgery was the safest option. When non-surgical treatment is the chosen option because of a lack of symptoms, follow up must be planned for the long term. Figure 4
The split renal DMSA scan.
Figure 5 (A) VCUG shows bilateral Grade IVeV VUR and left duplex system with a blind-ended ureteral unit correspondent to the dysplastic lower pole. (B) Contrast CT-scan image, for comparison.
494
A. Iscaife et al.
Conclusion
References
We have described the 36th case of SMDK, a rare multicystic dysplasia condition presenting with urosepsis. Thus far, surgical treatment seems to be the best indication with special attention to associated abnormalities. Long-term follow up will shed more light upon the natural history of this type of kidney dysplasia.
[1] Kalyoussef E, Hwang J, Rasad V, Barone J. Segmental multicystic dysplastic kidney in children. Urology 2006;68:1121.e9e1121.e11. [2] Eckoldt F, Woderich R, Smith RD, Heling KS. Antenatal diagnostic aspects of unilateral multicystic kidney dysplasia e sensitivity, specificity, predictive values, differential diagnoses, associated malformations and consequences. Fetal Diagn Ther 2004;19:163e9. [3] Lin CC, Tsai JD, Sheu JC, Lu HJ, Chang BP. Segmental multicystic dysplastic kidney in children: clinical presentation, imaging finding, management, and outcome. J Pediatr Surg 2010;45:1856e62. [4] Murer L, Benetti E, Artifoni L. Embryology and genetics of primary vesico-ureteric reflux and associated renal dysplasia. Pediatr Nephrol 2007;22:788e97.
Conflict of interest/funding None.