Wallach's Interpretation of Diagnostic Tests: Pathways to Arriving at a Clinical Diagnosis (91 page)

   Serology and/or culture may be helpful in identification of infection (herpes zoster, benign polyneuritis associated with cervical lymph node TB, or Lyme disease).

   Tissue biopsy of the nerve or adjacent soft tissues may diagnose sarcoidosis and tumors (meningioma, neurofibroma, carcinoma, cholesteatoma, chordoma).

   Imaging studies are most useful for the detection of trauma and aneurysms.

MONONEUROPATHY

   Definition

Mononeuropathy is defined as the focal dysfunction of a single nerve and may be due to trauma or compression such as carpal tunnel syndrome. Mononeuropathy multiplex is the involvement of several noncontiguous nerves.

   Clinical Presentation

Patients present with various symptoms such as pain, paresthesias, or weakness relating to the nerve that is involved. Mononeuropathy may be due to a systemic vasculitic process that affects the vasa vasorum resulting in multiple infarcts. Other causes of mononeuropathy include

   DM

   Infections (e.g., HIV, diphtheria, herpes zoster, leprosy)

   Sarcoidosis

   Polyarteritis nodosa

   Tumor (leukemia, lymphoma, carcinomas)

   Trauma

   Serum sickness

   Bell palsy