Increased plasmin-mediated proteolysis of L1CAM in a mouse model of idiopathic normal pressure hydrocephalus.

Idiopathic normal pressure hydrocephalus (iNPH) is a common neurological disorder that is characterized by enlarged cerebral ventricles, gait difficulty, incontinence, and dementia. iNPH usually develops after the sixth decade of life in previously asymptomatic individuals. We recently reported that loss-of-function deletions in CWH43 lead to the development of iNPH in a subgroup of patients, but how this occurs is poorly understood. Here, we show that deletions in CWH43 decrease expression of the cell adhesion molecule, L1CAM, in the brains of CWH43 mutant mice and in human HeLa cells harboring a CWH43 deletion. Loss-of-function mutations in L1CAM are a common cause of severe neurodevelopmental defects that include congenital X-linked hydrocephalus. Mechanistically, we find that CWH43 deletion leads to decreased N-glycosylation of L1CAM, decreased association of L1CAM with cell membrane lipid microdomains, increased L1CAM cleavage by plasmin, and increased shedding of cleaved L1CAM in the cerebrospinal fluid. CWH43 deletion also decreased L1CAM nuclear translocation, suggesting decreased L1CAM intracellular signaling. Importantly, the increase in L1CAM cleavage occurred primarily in the ventricular and subventricular zones where brain CWH43 is most highly expressed. Thus, CWH43 deletions may contribute to adult-onset iNPH by selectively downregulating L1CAM in the ventricular and subventricular zone.

Bacterial translocation as a cause of ventriculoperitoneal shunt infection: A case report.

Bacterial translocation as a mechanism of distal catheter infection may play a larger role in ventriculoperitoneal shunt infections than previously recognized.

Ventriculogallbladder Shunt: Percutaneous Transhepatic Placement of the Distal Catheter.

BACKGROUND: Ventriculogallbladder (VGB) shunts are currently placed as a salvage procedure in treatment of hydrocephalus when all other options are exhausted. Although VGB shunts work well when successfully implanted, they are still rarely used because of the technical challenges with the traditional surgical technique. OBJECTIVE: To implant VGB shunts using a minimally invasive technique that is safer and less technically challenging. METHODS: We discussed our utilization of a percutaneous transhepatic approach to placement of the distal catheter into the gallbladder as a new technique that offers a solution to the established but surgically demanding current approach. We presented a complex patient with multiple failed shunts who underwent placement of a VGB shunt. RESULTS: The shunt was successfully placed and did not incur any complications or require any revisions in 5 yr. CONCLUSION: Given the safety and ease of this minimally invasive approach, we believe percutaneous transhepatic approach in VGB shunts should be considered as a reasonable option in patients with complex hydrocephalus.

Spontaneous Propionibacterium Acnes abscess with intraventricular rupture in an immunocompetent adult without prior neurosurgical intervention.

Previously viewed as a culture contaminant, Propionibacterium Acnes can cause infection following neurosurgical intervention. Its role in brain abscess in the immunocompetent, surgically naïve population has been infrequently reported. Herein, we describe an immunocompetent 55-year-old man with no risk factors found to have a thalamic abscess with intraventricular rupture.

Evidence for increased intraabdominal pressure as a cause of recurrent migration of the distal catheter of a ventriculoperitoneal shunt: illustrative case.

BACKGROUND: Placement of a ventriculoperitoneal (VP) shunt is an effective treatment for several disorders of cerebrospinal fluid flow. A rare complication involves postoperative migration of the distal catheter out of the intraperitoneal compartment and into the subcutaneous space. Several theories attempt to explain this phenomenon, but the mechanism remains unclear. OBSERVATIONS: The authors report the case of a 37-year-old nonobese woman who underwent placement of a VP shunt for idiopathic intracranial hypertension. Postoperatively, the distal catheter of the VP shunt migrated into the subcutaneous space on three occasions despite the use of multiple surgical techniques, including open and laparoscopic methods of abdominal catheter placement. Notably, the patient repeatedly displayed radiographic evidence of chronic bowel distention consistent with increased intraperitoneal pressure. LESSONS: In this case, the mechanism of catheter migration into the subcutaneous space did not appear to be caused by pulling of the catheter from above but rather by expulsion of the catheter from the peritoneum. Space in the subcutaneous tissues caused by open surgical placement of the catheter was permissive for this process. Patients with chronic increased intraabdominal pressure, such as that caused by bowel distention, obesity, or Valsalva maneuvers, may be at increased risk for distal catheter migration.