Keywords
ventriculoperitoneal shunt - intestinal perforation - hydrocephalus
Introduction
Ventriculoperitoneal shunt (VPS) has become the standard treatment for congenital
hydrocephalus since its introduction into the neurosurgical practice in the 1950s.[1]
Although uncommon, several abdominal complications resulting from VPS have been described,
including fibrous entrapment of the catheter, blocking or twisting of the distal tube,
extrusion by surgical incision, or migration of the shunt to a cavity other than the
peritoneal one.[2] Intestinal perforation presents an incidence of 0.1% to 1% of the cases of catheter
displacement, which can lead to infections, meningitis, seizures, fever and increased
intracranial pressure, as well as abdominal manifestations, such as intestinal obstructions
associated with adhesions, inflammatory pseudocysts and ascites.[3] Despite the low incidence, when perforation is associated with infections, it is
related to a mortality of up to 15%.[4]
The aim of the present study is to report an unusual case of an adult patient with
intestinal perforation and spontaneous extrusion of the VPS catheter through the anus.
Case Report
A 19-year-old female patient underwent a VPS implant at the age of 2 due to congenital
hydrocephalus. Over time, it evolved with a delay in neuropsychomotor development
and bed restriction. At the age of 13, she underwent an open appendectomy, evolving
in the postoperative period with obstruction and infection of the implant site of
the VPS, and a shunt review was performed.
Six years later, when the patient was aged 19 years, her caregiver noticed exposure
of the distal end of the VPS catheter through the patient's anus ([Fig. 1]), which motivated her return to the neurosurgery service. Upon physical examination,
the tip of the extruded VPS catheter was found 5 cm from the anal margin, without
dripping cerebrospinal fluid (CSF). Signs of phlogistic skin were detected in the
cervical path of the VPS, but she did not have fever, abdominal distension, pain on
palpation of the abdomen, ascites, vomiting or headache, and peritonitis or encephalitis
were ruled out.
Fig. 1 Exposure of the distal end of the ventriculoperitoneal shunt catheter through the
patient's anus.
An abdominal computed tomography (CT) scan showed that the catheter path had no evidence
of knots or pneumoperitoneum. Moreover, this image showed the peritoneal catheter
perforating the descending colon and being extruded through the anus. The patient
underwent surgery to remove the proximal portion of the VPS and to implant an external
ventricular drain (EVD), without complications ([Fig. 2] and [3]).
Fig. 2 Abdominal computed tomography scan showing the peritoneal catheter perforating the
descending colon.
Fig. 3 Abdomen computed tomography scan, after the surgery to remove the proximal portion
of the ventriculoperitoneal shunt and to implant an external ventricular drain (seven
days later), showing the peritoneal catheter being extruded through the patient's
anus.
During hospitalization, antimicrobial prophylaxis with ceftriaxone and vancomycin
was prescribed, the former being replaced on the seventh day by meropenem. While evaluating
the possibility of laparoscopic exploration with the general surgery team, the patient
spontaneously expelled the distal portion of the catheter on the ninth day of hospitalization
([Fig. 4]). A new abdominal CT scan was requested, and no abscesses or signs of infection
were noted. The CSF culture did not show bacterial growth, but showed normal glucose
levels. With antimicrobial prophylaxis and the contralateral VPS performed, the patient
evolved without further complications until discharge.
Fig. 4 The patient spontaneously expelled the distal portion of the catheter on the ninth
day of hospitalization.
Discussion
Spontaneous intestinal perforation is an extremely uncommon complication, which was
first reported by Wilson and Bertran[5] in 2 pediatric patients in 1966. From the initial report to the present day, approximately
112 cases of intestinal perforation associated with a VPS have been reported in the
literature, half of them in patients aged up to 10 years. The combination of thin
intestinal musculature in the myelomeningocele, placement of rigid peritoneal catheters,
and local infectious adhesions can predispose intestinal perforation.[3]
In cases submitted to surgical intervention or autopsy, the authors[4] have described a fibrotic scar that anchors the tube in an region of the intestine
and causes ulceration and, theoretically, eventual perforation.
Although not found in the case herein reported, significant abdominal symptoms or
peritonitis affect up to 25% of the cases.[6] Surgeons must be aware of this complication to prevent the development of infections
such as meningitis, ventriculitis and sepsis, which are associated with mortality
in up to 15% of the cases.[4]
In the presence of pneumoperitoneum, radiographs can confirm the diagnosis of intestinal
perforation. The exam also shows the trajectory of the peritoneal catheter to the
perineal region. Meanwhile, abdominal CT scans enables physicians to rule out the
presence of abscesses, in addition to suggesting a more precise location for the point
of perforation.[7] In view of the evidence, these were the tests chosen for the assessment of the case
herein reported. Although there was no pneumoperitoneum, the radiographs enabled the
observation of the catheter path, while the abdominal CT scan showed perforation in
the descending colon.
The management of intestinal perforation is individualized and depends on the signs
and symptoms of the patient. In a patient with intestinal perforation, but without
other complications, a formal exploratory laparotomy is not necessary. Our patient
fits into the subset of patients who can, therefore, be treated without laparotomy,
by means of externalization of the ventricular shunt and antimicrobial prophylaxis
until the CSF bacteriological cultures become negative. It is important to emphasize
that, when making a new derivation, it is recommended to choose a different terminal
of the abdominal cavity, as there is a concern that the factors that triggered the
perforation may still be present.[8]
If there is concern about abdominal abscess or peritonitis, laparotomy is the preferred
treatment to control bacterial infection.[9] In some cases, the knot of the long shunt catheter itself or tangling of the tube
in the intestinal loops makes laparotomy mandatory, even in the absence of peritonitis.
As an alternative, laparoscopic visualization and disconnection of the derivation
tube can be performed.[10]
Although intestinal perforation is a complication already reported in the literature,
we have not identified any reports of spontaneous anal extrusion from the distal portion
of the catheter after surgical removal of the proximal portion and antimicrobial prophylaxis.
Assessing the infection-free evolution of the patient, this strategy can avoid unnecessary
laparotomies, reducing the cost, the risk of infections, and excessive invasive interventions
in patients who are often debilitated.
Conclusion
Intestinal perforation with anal catheter extrusion is an uncommon complication, usually
asymptomatic, more common in children, and which has a good prognosis in most cases.
In the case herein reported, its treatment consisted of removing the proximal portion
of the catheter and administering antibiotics. Laparotomy with repair of the perforation
should be performed mainly in cases of peritonitis, intra-abdominal abscess, or catheter
tangling. Knowledge of this atypical complication and of the natural evolution will
enable early recognition and more accurate surgical indications.
