Medullary sponge kidneypart of a congenital syndrome
(Section Editor: K. Kühn)
Denis Rommel and
Yves Pirson
Cliniques Universitaires St-Luc, Department of Nephrology, Université Catholique de Louvain, Brussels, Belgium
Case
A 25-year-old woman was referred to our department for recurrent acute pyelonephritis of the left kidney. A first episode had been treated 2 months earlier with amoxycillin for 3 weeks. Urinalysis showed 60 white blood cells per high-power field and >106 E. coli. Serum creatinine level was 1 mg/dl. Serum electrolytes were Na 139, K 4.2, HCO3 23.5, Cl 105 mmol/l. C-reactive protein was elevated (14.3 mg/dl) as well as neutrophil count (9.600/mm3). The patient was successfully treated with norfloxacin for 3 weeks.
Physical examination revealed a right body hemihypertrophy, as evidenced in the face (cheekbones, tongue) and both the upper and lower limbs (causing scoliosis) (Figures 14


).
Past history reveals that at the age of 5 years the patient had presented with an acute abdominal syndrome due to a tumour of the right kidney. A nephroblastoma was diagnosed and total nephrectomy was performed. Pathological examination confirmed the diagnosis of Wilms' tumour. She was given complementary treatment with chemotherapy and radiotherapy. There was no recurrence. An intravenous pyelogram (IVP) revealed no abnormality in the left kidney.
Five years before admission an IVP, performed because of recurrent lower urinary tract infection, showed both linear striations and accumulation of contrast in small cysts within the papillae of the lower pole of the remaining kidney, characteristic of a localized form of medullary sponge kidney (MSK) (Figure 5
). Notably, the patient never passed calculi nor experienced renal colic.

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Fig. 5. Intravenous pyelogram showing accumulation of contrast in multiple small cysts involving the lower pole of the left kidney giving to the papillae the appearance of a bouquet of flowers, characteristic of MSK.
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Discussion
This patient has clearly developed a MSK involving the remaining kidney in a context of congenital hemihypertrophy (CHH) and a history of Wilms tumour. That this triple association is not fortuitous is suggested by two previous reports [1,2].
MSK refers to a specific morphological abnormality of the kidney characterized by ectatic and cystic changes of the medullary collecting ducts. Common complications are infection and calcium stones. The estimated prevalence of MSK in the general population ranges between 5 in 10 000 [3] and 5 in 100 000 [4]. MSK occurs more frequently among individuals with other congenital defects (Table 1
). Among the various congenital disorders associated with MSK, the most frequent is CHH. Five to ten per cent of patients with CHH are found to have MSK [5].
CHH is characterized by asymmetry of the body as a result of hypertrophy of all somatic elements of one or more body parts [6]. Its estimated prevalence is 1 in 40 000 live births [7]. The developmental defect causing CHH has yet to be elucidated. Interestingly, CHH predisposes to childhood tumours, particularly adrenal adenomas and Wilms tumours [7]. Of 108 patients with CHH, 3.8% developed tumours [8]. Conversely, 2.6% of patients with Wilms tumour were found to have CHH [1].
Taken together, these data strongly suggest that the triad MSKCHHWilms tumour observed in our patient is interrelated. Such an association has been reported in only two cases (Table 2
), to the best of our knowledge. In a series of seven infants with CHH and associated abdominal lesions, Hennessy et al. [2] mentioned the case of 2-year-old infant with left CHH in whom a Wilms tumour and MSK were found at age 9 in left and right side respectively. In 1991, Beetz et al. [1] reported on a 1-year-old girl with CHH and bilateral MSK in whom a Wilms tumour was diagnosed at age 6. Notably, in this infant, CHH was part of a BeckwithWiedemann syndrome (BWS).
The BWS is a congenital overgrowth syndrome comprising multiple anomalies including high birth weight, macroglossia, ear abnormalities, omphalocoele, visceromegaly, somatic asymmetry, MSK, and an increased risk of developing various tumours such as Wilms' tumour, adrenal carcinoma, hepatoblastoma, pancreatic cancer, and neuroblastoma [9]. Interestingly, some affected patients may have a mild form of the BWS, only apparent after a careful review of history and clinical examination: thus, in a 15-year-old girl reported by Chesney et al. [10], clinical features of the BWS were restricted to a high birth weight, ear abnormalities, and MSK. This leads us to suggest that the triad present in our patient might be a limited form of the BWS. There is increasing evidence that the gene for the BWS is located on chromosome 11p15, within a cluster of imprinted genes [11]. The most intensively studied candidate gene is IGF2 [11]. Only the elucidation of molecular genetics of the BWS will demonstrate if the triad observed in our patient is a minor form of the BWS.
Teaching points
- (i) Medullary sponge kidney may be associated with a variety of congenital abnormalities, including congenital hemihypertrophy and the BeckwithWiedemann syndrome, sometimes clinically subtle.
- (ii) A child with evidence of congenital hemihypertrophy has an increased risk of developing both an embryonal tumour, especially Wilms' tumour, and medullary sponge kidney.
Notes
Supported by an educational grant from

Fresenius Medical Care
Correspondence and offprint requests to: Yves Pirson MD, Cliniques Universitaires St-Luc, av. Hippocrate 10, B-1200 Bruxelles, Belgium. 
References
-
Beetz R, Schofer O, Riedmiller H, Schumacher R, Gutjahr P. Medullary sponge kidneys and unilateral Wilms tumour in a child with BeckwithWiedemann syndrome. Eur J Pediatr1991; 150: 489492[ISI][Medline]
-
Hennessy WT, Cromie WJ, Duckett JW. Congenital hemihypertrophy and associated abdominal lesions. Urology1981; 18: 576579[ISI][Medline]
-
Gardner KD Jr. Medullary sponge kidney. In: Edelmann CM Jr, ed. Pediatric Kidney Disease. Little, Brown, Boston, 1992; 16411645
-
Mayall GF. The incidence of medullary sponge kidney. Radiology1970; 21: 171174
-
Hildebrandt F, Jungers P, Grünfeld JP. Medullary cystic and medullary sponge renal disorders. In: Schrier RW, Gottschalk CW, ed. Diseases of the Kidney. Little, Brown, Boston,1997; 499520
-
Indridason OS, Thomas L, Berkoben M. Medullary sponge kidney associated with congenital hemihypertrophy. J Am Soc Nephrol1996; 7: 11231130[Abstract]
-
Bueno I, Ventura P, Samper MP, Perez Gonzalez JM, Bueno M. Congenital hemihypertrophy. Genet Couns1993; 4: 231234[Medline]
-
Cohen MM Jr. A comprehensive and critical assessment of overgrowth and overgrowth syndromes. Adv Hum Genet1989; 19: 181376
-
Engström W, Lindham S, Schofield P. WiedemannBeckwith syndrome. Eur J Pediatr1988; 147: 450457[ISI][Medline]
-
Chesney RW, Kaufman R, Stapleton FB, Rivas ML. Association of medullary sponge kidney and medullary dysplasia in BeckwithWiedemann syndrome. J Pediatr1989; 115: 761764[ISI][Medline]
-
Maher ER, Reik W. BeckwithWiedemann syndrome: imprinting in clusters revisited. J Clin Invest2000; 105: 247252[Free Full Text]