Mohammed T. Abou-Saleh

342 PRINCIPLES AND PRACTICE OF GERIATRIC PSYCHIATRYTable 61.1Peripheral neuropathy: etiology and classification1. Neuropathy associated with toxic metabolic statesA. Vitamin deficiency (B 1 ,B 12 ,B 6 , nicotinic acid, pantothenic acid andfolic acid)B. DiabeticC. UremicD. HepaticE. Thyroid diseaseF. Dysproteinemias and paraproteinemiasG. AlcoholH. Amyloid2. Inherited peripheral neuropathyA. Charcot–Marie–ToothB. Dejerine–Sottas (hypertrophic)C. Roussy–Le´vyD. Refsum’s diseaseE. Tangier disease and Ab-lipoproteinemia (Bassen–Kornzweig’s)F. Neuropathy associated with the leukodystrophies (metachromaticleukodystrophy, Krabbe’s disease, adrenoleukodystrophy)G. Fabry’s diseaseH. Porphyric neuropathyI. Friedreich’s diseaseJ. Tomaculous neuropathy3. Infectious, inflammatory and post-infectious neuropathyA. Guillain–Barré syndrome, inflammatory polyradiculoneuropathyB. DiphtheriaC. LeprosyD. SarcoidE. CIDP (chronic inflammatory)F. AIDSG. Campylobacter4. Neuropathies associated with malignancyA. Neuropathy associated with lymphoma and Hodgkin’s disease(sensory, motor, mixed)5. Toxic neuropathiesA. Heavy metals1. Lead2. Arsenic3. Mercury4. ThalliumB. Toxins1. Acrylamide2. Trichloroethylene3. Benzene4. Carbon tetrachloride5. TOCP (triorthocresyl phosphate)C. Drugs1. Vincristine, vinblastine2. Chloroquine3. Nitrofurantoin4. Phenytoin5. Disulfiram6. Isoniazid7. Thalidomide8. Excessive B 6 administration9. Dapsone10. Amioderone11. cis-platinburning or numbness and tingling in the toes and feet, and lesscommonly the hands, are present. Often a ‘‘stocking glove’’distribution of decreased pain, temperature and vibration perceptionis present, along with decreased distal reflexes.Patients with longstanding diabetes or poor glucose controlusually have more severe neuropathy, although these do notalways correlate well. In addition, mononeuropathy (involvementof single motor or sensory nerves) is frequently seen in diabetes.Femoral neuropathy produces pain in the anterior medial thigh,with weakness in the proximal muscles of the leg. Lumbosacralplexus involvement with weakness and atrophy of the thighmuscles is termed diabetic amyotrophy. Mononeuritis multiplexinvolves multiple sensory and motor nerves in an asymmetricalfashion, usually due to infarction of the nerves. However, multiplemononeuropathies may also occur, due to pressure or entrapment.These need recognition so that patients can be taught howto prevent further trauma or compression of their nerve.Radiculopathy in the thoracic or lumbar area without discherniation also occurs frequently in diabetes. In the thoracic area,patients complain of chest wall or abdominal pain, usuallyunilaterally, and may have abdominal musculature weakness. Theautonomic nervous system may also be involved, causingorthostatic hypotension, bladder and gastrointestinal disturbances,skin changes, sweating abnormalities and impotence. Apenile prosthesis may be helpful in male patients with impotence.Alcoholic Neuropathy (Nutritional/Toxic)This neuropathy is most often sensory, with pain on the soles ofthe feet and loss of ankle reflexes. Minor motor involvement mayoccur, but is seldom severe. This is associated with vitamin B 1deficiency, but is also likely a direct toxic effect from chronicalcohol use. A history of the amount and frequency of alcoholintake is essential in evaluating these problems. Abstinence fromalcohol is necessary to result in any improvement. Psychiatric careis usually the predominant need in these patients, however.Evaluation of Patients with NeuropathyEvaluation for systemic disease in patients with peripheralneuropathy must include several factors: patient history, physicalexamination, basic laboratory studies and special laboratoryanalysis.The history should include a detailed family history, but thismay be difficult to obtain. Sometimes additional family membersmust also be examined. The social history should includeoccupation, types of hobbies and possible exposure to toxins.Other medical illness should be noted. A complete record of alldrugs used, including prescription, non-prescription and recreationaldrugs, should be obtained. One should determine whetheronset of symptoms correlates with initiation of a drug regimen.Recent medical history should include risk factors for possibleinfectious etiologies, such as tick exposure, high-risk sexualTable 61.2Approach to history in peripheral neuropathyFamily history: diabetes mellitus, pernicious anemia, amyloidosis, porphyria,Refsum’s disease, Tangier diseaseSocial history: alcoholism, occupation or hobbies with possible toxicexposure (carbon tetrachloride, carbon disulfide, carbon monoxide,trichloroethylene, trinitrotoluene, benzene, o-dinitrophenol, lead,arsenic, bismuth, mercury, thallium, copper, silver, gold, antimony,zinc), intentional poisoning (suicide, homicide), heavy smoking(carcinoma of lung)Medication history: sulphonamides, emetine, hydralazine, nitrofurantoin,diphenylhydantoin, glutethimide, isoniazid, allopurinol, thalidomide,insulinRecent medical history: infections (AIDS, diphtheria, tuberculosis,infectious mononucleosis, infectious hepatitis, syphilis, typhoid,typhus, ‘‘strep throat’’, cat-scratch fever), malignancy (directinvasion or remote effects), gastrointestinal disturbances (seen witharsenic, lead, porphyria, thallium, vitamin deficiencies, perniciousanemia, hepatitis, Tangier disease)