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ORIGINAL ARTICLE
Congenital absence of the vas deferens and unilateral renalagenesis: implications for patient and family
Victoria Alison Lane • Simon Scammell •
Noreen West • Govind V. Murthi
Accepted: 22 May 2014 / Published online: 31 May 2014
� Springer-Verlag Berlin Heidelberg 2014
Abstract
Background and aims At routine groin surgery in male
paediatric patients occasionally the vas deferens may be
absent. This finding usually leads to investigations to estab-
lish the status of the contralateral vas deferens and the status
of the kidneys. It is not uncommon to find either an ipsilateral
renal agenesis or congenital bilateral absence of the vas
deferens. The latter finding prompts a test for cystic fibrosis.
We report three patients who upon investigation were found
to have the rare combination of congenital bilateral absence
of the vas deferens and unilateral renal agenesis, and discuss
the possible embryological basis, the clinical management
and the long-term implications of these findings.
Patients and methods We present three patients who were
incidentally found to have absence of the vas deferens
whilst undergoing elective groin surgery and following
further tests were diagnosed with congenital bilateral
absence of the vas deferens and unilateral renal agenesis.
The case notes were reviewed, together with the results of
radiological investigations, cystic fibrosis screening and the
status of the contralateral vas deferens.
Results All three patients were found to have congenital
bilateral absence of the vas deferens, unilateral renal
agenesis and were not found to have cystic fibrosis.
Conclusions The combination of congenital bilateral
absence of the vas deferens and unilateral renal agenesis,
without cystic fibrosis, is rare and not reported previously
in the paediatric literature. These findings require appro-
priate counselling of the parents and child, with regards to
the long-term implications of infertility and renal function.
Keywords Absent vas deferens � Renal agenesis �Congenital
Introduction
Groin surgery is commonly undertaken in male paediatric
patients for the correction of inguinal hernia, hydrocele or
the undescended testis. Occasionally, absence of the vas
deferens will be demonstrated and many paediatric sur-
geons will simply perform a renal ultrasound to look for
ipsilateral renal agenesis. We feel that it is also important to
establish the status of the contralateral vas deferens (by
concomitant laparoscopic evaluation or contralateral groin
exploration) in addition to looking for abnormal renal
anatomy. The finding of congenital bilateral absence of vas
deferens (CBAVD) will automatically lead to the child
being screened for cystic fibrosis (CF). On rare occasions,
however, these investigations will reveal the unusual
combination of CBAVD and unilateral renal agenesis
(URA). Here, we report three patients diagnosed with
CBAVD and URA and discuss the possible embryological
basis for the uncommon entity, the clinical management
pathway and the long-term implications of these findings.
Cases
Case I
An 18-month-old boy, previously known to have a solitary
left kidney, was referred with an undescended left testis.
He underwent a left orchidopexy at the age of 2 years,
when an absent left vas deferens was noted. At routine
outpatient review 6 months later, the testis had re-
V. A. Lane (&) � S. Scammell � N. West � G. V. Murthi
Sheffield Children’s Hospital, Sheffield, UK
e-mail: vic4lane@btinternet.com
123
Pediatr Surg Int (2014) 30:733–736
DOI 10.1007/s00383-014-3522-x
ascended, and was palpable in the groin. At the time of
repeat orchidopexy, laparoscopy confirmed the presence of
bilateral absence of the vas deferens. A left orchidectomy
was performed, and histology confirmed a normal testicle
with rudimentary epididymis. Cystic fibrosis screening for
the common Western Europe mutations and a subsequent
sweat test were negative.
Case II
A 2-month-old male infant born at 34/40 with an antenatal
history of maternal drug use and intrauterine growth
restriction was diagnosed post natally to have a left inguinal
hernia and was referred for surgical assessment. At laparo-
scopic hernia repair, he was found to have bilateral inguinal
herniae and CBAVD. On renal USS, he was found to have
left renal agenesis. CF screening was negative.
Case III
A 2 � year old boy underwent surgery for an undescended
right testis. At operation, he was found to have an absent
right vas deferens. Laparoscopy was performed and con-
firmed CBAVD and renal USS showed right renal agenesis.
CF screening was negative.
These clinical findings and investigations are summa-
rised in Table 1.
Discussion
Embryology
Development of the genital system is closely integrated
with the developing renal system. Three systems
develop from the intermediate mesoderm: (1) the cer-
vical nephrotomes (which are non-functioning), (2) the
mesonephros which functions briefly in fetal life and
(3) the sacral metanephric system, which forms the
definitive kidneys.
The mesonephros and the mesonephric ducts develop
simultaneously, following involution of the initial cervical
nephrotomes in the intermediate mesoderm. Early in the
4th week of gestation, the mesonephric tubules develop
within the mesonephros (the lateral tip of each meso-
nephric tubule fuses with a mesonephric duct) forming an
excretory unit, which functions from weeks 6–10 and then
regresses. In the female, the mesonephric ducts also
regress; however, in the male, the mesonephric ducts per-
sist to form the genital duct system. The final renal system
is dependent on the ingrowth of the branching ureteric buds
into the metanephric blastema, giving rise to the charac-
teristic lobulated appearance we recognise as the definitive
kidney.
Each mesonephric duct, in the male, has two derivatives:
(1) the ipsilateral ureteral/renal system and (2) the ipsilat-
eral vas deferens, seminal vesicle and distal two-thirds of
the epididymis. The physical separation of these two limbs
occurs at about 7 weeks of gestation [1]. If an insult,
whether genetic or toxic in nature, occurs prior to week 7,
the entire mesonephric duct and its derivatives will be
adversely affected. If the insult occurs after this time per-
iod, only one of the two bi-products may be affected. It is
thus postulated that in patients with CBAVD/URA, the
insult has occurred after 7 weeks of gestation, leading to
absence of the vas deferens and the ipsilateral renal unit
with preservation of the contralateral renal unit. The reason
for the insult affecting both derivatives on one side and
only the vas deferens on the contralateral side, leading to
CBAVD/URA, remains elusive.
Since males afflicted with clinical CF and bilateral
absence of the vas deferens have normal renal anatomy,
CFTR mutations probably do not affect the primitive
mesonephric duct, and may exert their effect only on the
developing reproductive ductal derivatives including the
vas deferens, seminal vesicle and distal epididymis [2].
One theory postulates that atrophy and involution of the
vas deferens and epididymal structures is caused by pro-
gressive obstruction of the genital duct by mucus and
secretory protein accumulation, as a similar process to this
Table 1 Patient summary Patient Presentation and
findings
Renal USS CF screening Sweat
test
1.Term infant Left
Undescended testis
Right
Renal agenesis
Normal CFTR screen for the
common Western Europe
mutations
Negative
2.34/40 gestation Left
Inguinal hernia
Left
Renal agenesis
Normal CFTR screen for the
common Western Europe
mutations
Negative
3.Term infant Right
Undescended testis
Right
Renal agenesis
Normal CFTR screen for the
common Western Europe
mutations
Negative
734 Pediatr Surg Int (2014) 30:733–736
123
is seen in the pancreas in those with CF [2]. Gaillard et al.
[2] studied the aborted fetuses at 12 and 18 weeks of
gestation, in those with an antenatal diagnosis of CF. No
abnormality was seen in the vas deferens, suggesting a later
insult, supporting this theory. However, patients with
CBAVD (without CF) do not have altered secretions con-
tradicting this theory and hence, the cause of the CBAVD
remains unclear.
In this regard, it is possible that men with CBAVD/
URA have a different genetic basis for their renal and
vasal agenesis, to men with CBAVD/CF with normal
renal anatomy. The presumed genetic anomaly would
disrupt precise morphogenesis of the early mesonephric
ducts. The most severe phenotypic manifestation would
be bilateral renal agenesis, whereas men with CBAVD/
URA obviously possess a less severe phenotype. The
transmission pattern has obviously been difficult to
establish, as these men are infertile. However, with the
advent of assisted reproduction techniques this is now
potentially possible.
Relation of CBAVD/URA to CF
Congenital bilateral absence of the vas deferens (CBAVD)
in isolation is associated, most commonly, with cystic
fibrosis (CF) and is recognised to occur in 98 % of males
with the disease and the associated infertility is well
recognised. Also, it is generally presumed that CBAVD
patients with abnormal renal anatomy do not have CFTR
gene mutations.
In 1994, Augarten et al. [3] identified 47 adult patients
with CBAVD and the results of subsequent investigations
are summarised below in Fig. 1. None of the 10 patients
with renal malformations had cystic fibrosis mutations, and
sweat chloride concentrations were normal, leading them to
suggest that CBAVD patients with renal malformations do
not necessarily have cystic fibrosis. This was supported by
subsequent studies [4, 5].
Robson et al. [6] stated that 70 % of boys with URA will
have congenital unilateral absence of the vas (CUAVD),
epididymis or seminal vesicle (CUAVD/URA), but the
finding of CBAVD/URA is more unusual. CFTR mutations
are generally not seen in this subset, and the pathophysi-
ology of boys with these combined abnormalities may not
be part of the CF mutation spectrum but may represent a
different, discrete clinical and genetic entity.
Whilst the various embryological and genetic hypothe-
ses suggest that CBAVD/URA has a different aetiological
basis to CBAVD associated with CF, of interest is the
report by Daudin et al. [7]. They have reported four adult
patients with the combination of CBAVD/URA. Two of
these patients in fact carried a CFTR gene mutation
(DF508/5T–9T and R117G/7T–9T) and the other two
patients were free of CFTR mutations and the 5T allele.
This finding shows that our understanding of the aetiology
of this condition is far from complete. On a clinical level, it
indicates the need to perform genetic testing in all patients
with CBAVD/URA as some may have associated
CF-related genetic abnormalities with implications for
47 patients with CBAVD
37 (79%) with normal
renal anatomy
10(21%)with renal malformations
18/37 (49%) CFTR mutation identified
17/26 (65%) High sweat chloride
10/10 (100%)No CFTR mutationidentified,Sweat chloridenormal
Fig. 1 Schematic representation of findings upon investigation of 47
patients with CBAVD by Augarten et al. [3]
Absent vas at groin exploration
Concomitant laparoscopic visualisation for status of
opposite vas+
Renal ultrasound scan
Bilateral absence of vas
Test for CF irrespective of renal status
Unilateral absence of vas Normal kidneys orUnilateral renal agenesis
Fig. 2 Recommended pathway
upon finding absent vas at groin
exploration
Pediatr Surg Int (2014) 30:733–736 735
123
counselling and further management not only of their
expected infertility, but also of the CF-related genetic
abnormalities.
Previously, the inheritance pattern of CBAVD was dif-
ficult to ascertain due to the functional infertility. However,
with the increased use of assisted conception, this is now
potentially possible. McCallum et al. [8] looked at the rates
of URA in the CBAVD population presenting with infer-
tility. They identified 168 men with CBAVD. The majority
of their patients 97 (58 %) had CBAVD, normal renal
anatomy and an identifiable CFTR mutation. 17/168
(10 %) had CBAVD/URA and no CFTR mutations. Two
men were found to have a pelvic kidney. The remaining 54
were excluded from the study because of inadequate data.
Of potential interest in this study, were the 17 men with
CBAVD/URA, as 12 opted for assisted conception
enabling possible inheritance patterns to be ascertained.
Family members were screened for abnormal renal anat-
omy (15 parents, 15 siblings, 10 conceptions and 3 nieces/
nephews). One fetus was found to have bilateral renal
agenesis and the pregnancy was terminated. At post mor-
tem, the fetus was found to have complete renal agenesis,
absent ureters and absent vas deferens bilaterally. All other
relatives were normal, unfortunately drawing little
conclusion.
Patient management algorithm
When absence of vas deferens is identified at groin
exploration, we recommend the following sequence of
investigations as shown in Fig. 2.
Counselling issues in the paediatric population
Parents of patients with CBAVD/URA need counselling
for the long-term implications of infertility and a single
kidney. In our institution, they are counselled for these
issues by our Cystic Fibrosis team and the nephrologist,
respectively.
Conclusion
In conclusion, the exact pathophysiology of CBAVD
remains poorly understood. The findings of an absent vas
deferens, at the time of groin surgery, should prompt the
surgeon to: (1) explore the status of the contralateral vas
deferens, preferably by laparoscopy under the same general
anaesthetic, and (2) conduct a renal tract ultrasound scan.
The finding of CBAVD should prompt tests for CF, irre-
spective of the status of the kidneys. Where the rare
combination of CBAVD/URA is discovered appropriate
counselling should be arranged.
References
1. Gibbons MD, Chromic WJ, Duckett JW (1978) Ectopic vas
deferens. J Urol 120:597–604
2. Gaillard DA, Carre-Pigeon F, Lallemand A (1997) Normal vas
deferens in fetuses with cystic fibrosis. J Urol 158:1549–1552
3. Augarten A, Yahav Y, Kerem Bs et al (1994) Congenital bilateral
absence of the vas deferens in the absence of cystic fibrosis. Lancet
344:1473–1474
4. Dork T, Dworniczak B, Aulehla-Scholz C et al (1997) Distinct
spectrum of CFTR gene mutations in congenital absence of vas
deferens. Human Genet 100:371–374
5. Schwarzer JU, Schwarz M (2012) Significance of CFTR gene
mutations in patients with congenital aplasia of vas deferens with
special regard to renal aplasia. Andrologia 44:305–307
6. Robson WL, Leung AK, Rodgers RC (1995) Unilateral renal
agenesis. Adv Pediatr 42:575–592
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736 Pediatr Surg Int (2014) 30:733–736
123
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