Strep Infection Identified as Another Possible Cause of Secondary IH
January 1, 2006—In another study examining patients enrolled in the IH Registry, investigators at Ohio State University in Columbus discovered evidence that points to a possible link between Group A streptococcal infections and intracranial hypertension. The research is being led by Susan Benes, M.D.
Ayam Skaf, a member of the Benes lab group, discussed his hypothesis that a significant number of children, age 13 and younger, presenting with idiopathic intracranial hypertension may have had a preceding or concurrent streptococcal infection, which could make CSF outfl ow ineffi cient, at least temporarily. The reason for this altered fl ow may be due to an autoimmune or toxic response, or flow changes in the arachnoid granulations or cerebral venous system.
The study focused on 14 (8.4%) of 167 IIH cases with a close association to Group A streptococcal infections. Height, weight, spinal fluid opening pressure and indices, coagulation factors, autoimmune markers, therapies and visual outcomes were examined in all study participants. Most of the 14 strep-associated patients were slender, prepubescent children under the age of 13. All were treated with carbonic anhydrase inhibitors (CAI).
In six of the 14 cases, surgery (one LP shunt, five bilateral optic nerve sheath decompression) was necessary to protect vision. To treat the streptococcal infections, all patients were given antibiotics. There were also fi ve tonsillectomies, two sinus surgeries and one tympanic tube procedure. Two of the 14 required continuing treatment with CAIs, though none required further surgery.
None of the strep-associate patients had abnormal PTT, antithrombin III, Factor V Leiden, protein S, MTHFR mutation, lupus anticoagulant factor or a positive ANA. However, three of 10 (30%) tested had anti-phospholipid antibodies. They were not tested for Factor VIII levels.
Given these results, the investigators recommended that slender children presenting with idiopathic intracranial hypertension should be tested for streptococcal infection with either an ASO titer or a throat Rapid Strep strip. They also recommended testing for anti-phospholipids, along with an MRI/MRV to rule out masses and larger vein thrombosis.
They also emphasized the importance of treating Group A streptococcal infections, especially in children, since intracranial hypertension may prove to be an associated complication of a strep infection or its post-infectious aftermath.