Multiloculated hydrocephalus related to cerebrospinal fluid shunt infection

Summary This study is an attempt to establish that CSF shunt infection has a role in the aetiology of multiloculated hydrocephalus. The authors carried out a review of 12 cases of multiloculated hydrocephalus who were treated at King Khalid University Hospital between 1988–1994. The multiloculation appears to have developed following the shunt infection in all cases. The hydrocephalus was related to an intraventricular haemorrhage (IVH) in 9 patients and was congenital in 2 patients and post-meningitic in 1 patient. The shunt infection was caused by a gram-negative organism in 8 patients and duration of external ventricular drainage ranged from 9–24 (median 13) days. The diagnosis of multiloculated hydrocephalus was made on average 2 months after the shunt infection. In three patients endoscopic fenestration of intraventricular septations was attempted but was effective in only one case. The other patients were managed by two shunts (9 patients) and three shunts (2 patients). At a mean follow-up of 15 months, the shunt revision rate of the patients was 0.4/year. One patient died of multiple brain abscesses and 6 patients remain severely disabled. The poor outcome may also be related to the original IVH as well as the multiloculated hydrocephalus.The study also shows that patients with post-haemorrhagic hydrocephalus, who develop a shunt infection due to gram-negative organisms and in whom the CSF fails to be cleared of the infection following 12 days of external drainage appear to be at risk of developing multiloculated hydrocephalus.     

Antibiotic prophylaxis

Surgical site infection (SSI) is a common postoperative complication which leads to significant morbidity and mortality. The aim of antibiotic prophylaxis is to reduce the incidence of SSI by preventing the development of infection due to colonizing or contaminating organisms at the operative site. It is used as an adjunct to, rather than a replacement for, other evidence-based interventions to prevent wound infection, such as the use of skin antiseptics. The choice of antimicrobial agent(s) used is dependent on how ‘clean’ the operation is, the operative site (which determines the likely organisms), and a variety of patient factors including the presence of allergies and colonization with resistant organisms such as meticillin-resistant Staphylococcus aureus (MRSA). The practicalities of antibiotic prophylaxis administration are discussed. Not all operations require antibiotic prophylaxis; use of antibiotics in any context, including as prophylaxis, can be associated with adverse effects, specifically an increased risk of Clostridium difficile-associated diarrhoea (CDAD) and resistance development; prophylaxis should therefore be used responsibly. This article will address some of the common misconceptions about its use and special patient circumstances requiring deviation from the usual guidance.     

Radionuclide-imaging shuntography for the evaluation of shunt patency

Radionuclide-imaging shuntography using technetium 99m pertechnetate was performed 78 times in 43 pediatric patients to evaluate the patency of their cerebrospinal fluid shunts. The flow patterns of the isotope that best correlated with adequate shunt function were complete supine patency and immediate erect patency. Delayed erect patency and pump patency indicated inadequate shunt function. Deceptive patency, defined as a shuntogram that demonstrates patency by any mechanism but that fails to reflect the true functional state of the shunt system, was observed in 40% of all patent shuntograms. Causes of deceptive patency included intermittent shunt obstruction, partial shunt obstruction, and failure to provide complete anatomic information. Other factors important for the accurate interpretation of radionuclide-imaging shuntography included extravasation of isotope, peritoneal spread of the radioactivity, ventricular images, and failure to diagnose disconnection of the shunt.     

In vitro and in vivo efficacy of a rifampin-loaded silicone catheter for the prevention of CSF shunt infections

Summary Infection of cerebrospinal fluid (CSF) shunts is one of the major complications associated with their use and is usually managed by shunt removal, temporary insertion of an external drainage and implantation of a new shunt system. We have evaluated the efficacy of a rifampin-loaded silicone ventricular catheter to prevent bacterial colonization and infection in vitro and in an animal model.On the basis of an incorporation process a rifampin-loaded catheter was developed which is capable of releasing rifampin in bacteriocidal concentrations for 60 days and more. In a stationary bacterial adherence assay usingS. epidermidis as test strain, the colonization resistance of the device was demonstrated.To assess the capability of the catheter to prevent CSF shunt infections, a rabbit model was developed which allowed the establishment of a reliable and reproducible CSF infection by implantation of silicone catheters into the ventricle and inoculatingS. epidermidis (minimal dose 10⁶ cfu) orS. aureus (minimal dose 10³ cfu). Rifampinloaded catheters (12 animals inoculated with S. epidermidis, 8 animals inoculated with S. aureus) were compared with non-loaded (14 animals inoculated with S. epidermidis, 19 animals inoculated with S. aureus) control catheters, and infection was documented by clinical, microbiological and histological methods.In contrast to the control group, none of the animals with rifampin-loaded catheters showed clinical signs of infection. Furthermore, in none of the materials obtained after sacrifice of the animals (catheter, brain tissue, CSF, blood) could the infecting bacteria be cultured, whereas in materials from animals with the unloaded catheter the infecting strains could always be cultured from the catheter and from surrounding brain tissue. The histological examination of catheter-adjacent tissue supported these findings.We conclude that a rifampin-loaded silicone ventricular catheter is capable of completely preventing bacterial colonization and infection by staphylococci as the main causative organisms in CSF shunt infections and should be further evaluated in clinical trials.     

Clinical experience with a new pressure-adjustable shunt valve

Summary The pressure-adjustable valve system Codman Medos allows valve pressure adjustment in 18 steps between 30 and 200 mm H₂O. A series of 90 patients, 15 children and 75 adults, who were shunted with this new programmable valve, is reported. Indication for shunt insertion were various types of hydrocephalus in 79 cases, malfunction of a medium pressure membrane valve shunt system in 9 cases and an arachnoid cyst and pseudotumour each in one case. The valve pressure was programmed prior to insertion to 200 mm H₂O in the adults and according to age in children and was modified postoperatively according to the clinical course.Underdrainage with subdural fluid collections appearing in 5 patients could be managed by valve pressure adjustment alone in 2 cases. One malfunctioning of the valve mechanism was due to mechanical obstruction. At the time of follow-up, 7 to 29 months after operation, outcome was excellent in 64 patients, good with marked improvement but residual symptoms in 19 patients and unchanged in 7 patients.The possibility of adjusting the valve pressure to the patient's demands was frequently used in children and adult normal pressure hydrocephalus patients with satisfying clinical results.     

Frequency and causes of shunt revisions in different cerebrospinal fluid shunt types

Summary Shunt complications and revisions are common in hydrocephalic patients treated with a ventriculo-atrial or a ventriculo-peritoneal shunt. The reported revision rate differs very much but the rate of revision is close to 50% in many papers. Data from 884 hydrocephalic patients treated with various shunt types in the period 1958–1989 were recorded retrospectively in order to evaluate the frequency of revision for various shunt types and secondly to analyse the specific reasons for the shunt revisions.The rate of shunt revision was 45%. The Pudenz shunt was revised more often (62%) than the remaining shunt types. The Hakim and the Orbis-Sigma shunts had fewer revisions (35% and 27%, respectively) than the other observed shunt types. A defect of or an obstruction in the ventricular catheters was a frequent cause of revision followed by a defect or an obstruction of the distal catheter, a displacement of the distal catheter and an acute infection. Because of the higher rate of revision for the Pudenz shunt the rate of the above mentioned specific complications is also higher in most of the subgroups for that specific shunt type. Driven by these experiences it is reasonable to seek to develop and introduce new shunt types in an attempt to reduce the complication rate.     

The risk of intracranial infection in adults with hydrocephalus after ventriculoperitoneal shunt surgery: A retrospective study

Infection remains the most significant complication of ventriculoperitoneal shunt (VPS) surgery. The objective of this study was to investigate intracranial infections complicating VPS surgery in adults with hydrocephalus. Patients who underwent VPS surgery for hydrocephalus between 2000 and 2016 were included. Clinical data and follow‐up evaluations were examined and analysed retrospectively. A total of 502 patients with hydrocephalus who underwent VPS surgery were included. They were followed up for at least 2 years. Twelve patients with incomplete data were excluded. Four hundred and ninety patients were included in the final analysis. Twenty‐five cases of intracranial infection occurred, accounting for 5.1% of patients with VPS surgery. The mean age of the patients was 57.1 ± 10.1 years (range, 39–72 years). The incidence of intracranial infection in patients over 60 years of age was higher than that in patients under 60 years of age (P = .007). Age (P = .007), diabetes (P = .026), skin infection (P = .028), bed‐ridden (P = .007), and modified operation (P = .011) were highly correlated with the incidence of intracranial infection. The findings of this retrospective study show that age, diabetes, skin infection, bed‐ridden, and modified operation of hydrocephalus significantly and independently correlated with the incidence of infection. Prospective studies are needed to assess the relationship between the incidence of infection and risk factors in patients with hydrocephalus after VPS.     

Copious watery nipple discharge caused by a discontinuous ventriculoperitoneal shunt

Breast‐related complications of ventriculoperitoneal (VP) shunts are rare. We present a case of a woman with a VP shunt with copious watery nipple discharge following a fall. Shunt discontinuity was identified on a diagnostic mammogram, and the nipple discharge was confirmed to be cerebrospinal fluid (CSF). Symptoms resolved with shunt revision.     

A long-term complication of burying a shunt valve in the skull

One of the most common causes of shunt malfunction is infection; a major contributing factor to this infection in neonates is scalp necrosis over the valve site. One of the methods recommended to avoid this requires the burying of the valve in the skull bone. We present a case of a long-term complication from this procedure: the shunt slowly disconnected, over a prolonged period, leading to the formation of the fibrous tunnel which enabled the shunt to function intermittently. We recommend that the practice of burying the shunt into the skull bone is be reconsidered.     

Shunt malfunction in relation to shunt infection

Summary Ventriculo-peritoneal shunt malfunction may be caused by shunt infection which may not be clinically apparent as the cause of the malfunction by standard diagnostic criteria. This suggests that the real incidence of infected shunts might be higher than previously suspected. In order to study the relationship between infection and shunt malfunction, we followed a protocol over five years (54 V-P shunts) consisting of (1) removal of the malfunctioning shunt and replacement in the same surgical procedure with a new one or institution of an external ventricular drainage for 8 days (if there were clear signs of infection), (2) culturing of CSF and every part of the removed shunt, and (3) intravenous antibiotic treatment (Vancomycin 1g./12h + Ceftriaxone 1g./12h) for five days after the new V-P shunt had been inserted. In those cases in which an external ventricular drainage had been placed, its tip and a portion of the new V-P shunt were also cultured. The results showed that although CSF cultures were negative in 49/54 cases (90.7%), cultures of the removed shunts were positive in 32/54 (59.2%), most of them (21/32, 65.6%) for Staphylococcus coagulase negative organisms.The CSF samples obtained by puncturing the reservoir on admission to Hospital were positive only in 5 out of 54 cases (9.2%), only in those showing clinical features of infection. In the remaining cases, 27 out of 54 (50%) the CSF cultures were negative but the shunt cultures proved positive and required further treatment.For the newly inserted shunts (173) CSF was collected through the shunt during the surgical procedure, and a small piece of the extra-tube from the ventricular and from the peritoneal catheter were obtained and cultured. All the six shunts (6/173, 3.4%) that showed positive cultures after insertion had to be replaced within a period of three to four weeks due to malfunction (range 26±7 days), indicating that the systematic culture of CSF and tubing helps to predict which shunts will soon need to be replaced due to infection.We conclude that CSF culture alone does not rule out infection in cases of shunt malfunction. The percutaneous CSF obtained from the shunt reservoir on admission is particularly prone to show negative cultures even when the shunt is colonized by bacteria.     

Limitations of Neuroendoscopic Treatment for Pediatric Hydrocephalus and Considerations from Future Perspectives

Neuroendoscopy has become common in the field of pediatric neurosurgery. As an alternative procedure to cerebrospinal fluid shunt, endoscopic third ventriculostomy has been the routine surgical treatment for obstructive hydrocephalus. However, the indication is still debatable in infantile periods. The predictors of late failure and how to manage are still unknown. Recently, the remarkable results of endoscopic choroid plexus coagulation in combination with third ventriculostomy, reported from experiences in Africa, present puzzling complexity. The current data on the role of neuroendoscopic surgery for pediatric hydrocephalus is reported with discussion of its limitations and future perspectives, in this review.     

Cavum septi pellucidi as a cause of shunt dysfunction

Cavum septi pellucidi and cavum vergae are generally asymptomatic fluid collections between the leaves of the septum pellucidum and are present in approximately 15% of adult brains. There are occasional reported cases of symptomatic cysts arising in this area. This paper reports a case in which a cavum septi pellucidi was a cause of shunt malfunction. On an air ventriculogram this condition was initially confused with a subdural collection.     

Brucella meningoencephalitis associated with cerebrospinal fluid shunt in a child: Case report

Brucella meningoencephalitis is rare in young children. We describe a patient who developed Brucella meningoen-cephalitis at the age of 20 months while he had a ventriculoperitoneal shunt in situ for treatment of hydrocephalus. This patient was treated with streptomycin and rifampicin. The shunt was left in situ, and all the clinical and laboratory test abnormalities subsided with this management. We propose that in a patient with Brucella meningo-encephalitis, the cerebrospinal fluid shunt system can be left in situ and treatment with appropriate combination of antibiotics should prove to be successful.     

A modified technique for the construction of a lumbo-peritoneal shunt

Summary The use of Mishler's reservoir and Raimondi's spring peritoneal catheter prevents the usual complications of lumbo-peritoneal shunts. This procedure is recommended for those patients with pseudotumor cerebri whose intracranial hypertension threatens vision despite conservative therapy and repeated lumbar punctures. It can also be performed for communicating hy drocephalus.This paper was presented at the Annual Meeting of Neurological Surgeons of Switzerland, Bern, November 25, 1972.     

Commonly encountered central nervous system infections in the neurointensive care unit

The central nervous system (CNS) may be infected by a number of organisms including bacteria, viruses, fungi, and protozoa. Non-infectious causes such as autoimmune and vascular conditions may present with similar clinical syndromes necessitating the appropriate laboratory requests and good diagnostics. CNS infections are associated with significant morbidity and mortality, often requiring surgical intervention and admission to neurointensive care units. Common infection diagnoses seen in the neurointensive care unit include meningitis, ventriculitis, encephalitis and abscesses, including brain and spine. New and emerging pathogens in ITU settings include Candida auris and multi-resistant Gram negative bacteria, which are easily transmissible and may threaten the antimicrobial choices available for patients.     

Commonly encountered central nervous system infections in the neurointensive care unit

The central nervous system (CNS) may be infected by a number of organisms, including bacteria, viruses, fungi and protozoa. Non-infectious causes such as autoimmune and vascular conditions may present with similar clinical syndromes necessitating the appropriate laboratory requests and good diagnostics. CNS infections are associated with significant morbidity and mortality, often requiring surgical intervention and admission to neurointensive care units. Common infection diagnoses seen in the neurointensive care unit include meningitis, ventriculitis, encephalitis and abscesses, including brain and spine. New and emerging pathogens in ITU settings include Candida auris and multi-resistant Gram-negative bacteria, which are easily transmissible and may threaten the antimicrobial choices available for patients.     

Life-threatening complications during anaesthesia in a patient with a ventriculo-atrial shunt and pulmonary hypertension

A 6-year-old patient with hydrocephalus who underwent revision of a ventriculo-atrial shunt is described. Anaesthesia was complicated by the occurrence of systemic hypertension and arterial hypoxaemia. The patient was subsequently found to have pulmonary hypertension secondary to recurrent pulmonary thromboembolism. The pathophysiological mechanisms for the patient's deterioration are discussed and the anaesthetic management of children with pulmonary hypertension is outlined. It is concluded that patients with a ventriculo-atrial shunt who present for surgery should be screened carefully for the presence of pulmonary hypertension.