Increased cytokines/chemokines and hyponatremia as a possible cause of clinically mild encephalitis/encephalopathy with a reversible splenial lesion associated with acute focal bacterial nephritis.

OBJECTIVE: Clinically mild encephalitis/encephalopathy with a reversible splenial lesion (MERS), the second most common encephalopathy syndrome in Japan, is most often associated with viral infection. Bacterial MERS has been rarely reported but is mostly associated with acute focal bacterial nephritis (AFBN) for an unknown reason. We examined cytokines and chemokines in four MERS patients with AFBN to determine if they play an important role in the pathogenesis. METHODS: We examined the clinical charts and MRI results in four MERS patients with AFBN, and measured 10 cytokines and chemokines in serum and cerebrospinal fluid in the acute phase. These were analyzed using the Mann-Whitney U test, compared with the control group (cases with a non-inflammatory neurological disease). Longitudinal changes in the serum cytokine and chemokine levels were evaluated in two patients. RESULTS: Hyponatremia was observed in all four patients with MERS associated with AFBN (128-134 mEq/L). CSF analysis revealed increased cytokines/chemokines associated with Th1 (CXCL10, TNF-α, IFN-γ), T reg (IL-10), Th17 (IL-6), and neutrophil (IL-8 and CXCL1). In serum, upregulation was observed in those associated with Th1 (CXCL10, TNF-α, IFN-γ), Th17 (IL-6), and inflammasome (IL-1ß). The increased serum cytokines/chemokines in the acute stage normalized within 2 weeks in patients 1 and 2, so examined, in accordance with their clinical improvement. CONCLUSION: Increased cytokines/chemokines and hyponatremia may be factors that explain why AFBN is likely to cause MERS.

Shunt Nephritis: An Increasingly Unfamiliar Diagnosis.

BACKGROUND: Shunt nephritis is a rare, reversible immune-complex mediated complication of cerebrospinal fluid (CSF) shunt infection that can progress to end-stage renal disease and even death if diagnosis is delayed. CASE DESCRIPTION: The present case report details the manifestation and clinical course of shunt nephritis in a 50-year-old patient who presented with symptoms of nephrotic syndrome 30 years after ventriculojugular shunt placement. Diagnosis was delayed due to initial negative CSF and blood cultures, but a later CSF culture was positive for Propionibacterium acnes. After treatment with intravenous antibiotics and complete removal of shunt with subsequent replacement with a new ventriculoperitoneal shunt, the nephritic symptoms resolved, but the patient continued to have reduced kidney function consistent with stage IIIa chronic kidney disease. CONCLUSION: This case emphasizes the clinical importance of having a high index of suspicion in patients with a ventricular shunt who present with symptoms consistent with nephritis, even in the setting of negative cultures and delayed presentation.

Shunt nephritis associated with Moraxella bovis.

Moraxella bovis was repeatedly isolated from cerebrospinal fluid in a girl with two episodes of shunt nephritis. Clinical remission of nephritis was achieved only after shunt replacement. A list of about 20 infectious agents reported to date in patients with shunt nephritis is given. M. bovis is yet another agent previously not reported in patients with shunt nephritis.