Idiopathic hypertrophic pachymeningitis

 

  Dumont AS, Clark AW, Sevick RJ, Myles ST. Idiopathic hypertrophic pachymeningitis:  A report of two cases and review of the literature.

 

Background-- Authors note entity was described by Charcot and Joffroy, and that there are three forms:  spinal, intracranial and craniospinal (latter is rarer). 

 

Past cases were often attributed to specific etiologies but most recent cases are idiopathic after investigation.  Authors case 1 underwent 2 surgeries for biopsy/decompression , had persistent pain and numbness, but was non progressive for 15 years after one early relapse.  The second one received steroids after biopsy with resolution of symptoms and MRI changes.  Authors argue based on above that the condition is not autoimmune. 

 

Literature review suggested a worse prognosis for patients with "inflammatory signs" (fever, high sed rate, CRP, or elevated WBC). 

 

Associations include infections: syphilis, TB, HTLV-1, fungi; may be presenting sign of adjacent ear or sinus infection.  Autoimmune associations include RA, orbital pseudotumor, multifocal fibrosclerosis, MCTD, Wegener's granulomatosis.    The 23 reports run the gamut from marked to slight improvement to deterioration and late recurrence or surgical death. 

 

For interest, Charcot's clinical descriptors divided the spinal form into distinct stages: first intermittent radicular pain that later became continuous; then muscle weakness and atrophy; then spastic paralysis and loss of sphincter control.  Radicular signs can be confined to the upper extremities and evolve over weeks to months or even a year. 

 

The cranial form frequently presents with a headache, cranial neuropathies and ataxia. 

 

Authors emphasize the need for pathologic confirmation.