 Solution

General paresis combines progressive mental deterioration with a characteristic disorder of speech, fine movement and motor control. The historical phrase “general paralysis of the insane” does not mean complete, simultaneous immobility of every muscle.

Early changes may include impaired judgment, forgetfulness, altered personality, irritability, inappropriate confidence and loss of ordinary social restraint. Expansive or grandiose delusions are characteristic in some cases, but depression, suspiciousness or less spectacular cognitive failure can occur. Increasing dementia and reduced insight are more fundamental than any one extravagant belief.

The physical examination may disclose hesitating or slurred articulation, tremulous lips and tongue, facial tremor, deteriorating handwriting and impaired coordination of the hands. Gait becomes unsteady and weakness advances. Unequal or abnormally reacting pupils, altered reflexes and seizures may occur. Later disease can bring severe cognitive incapacity, swallowing difficulty, incontinence and dependence. Mental and motor manifestations need not develop in a fixed order or with equal severity.^[ref]

The name general paresis was already advocated in a January 1864 pathological study to avoid the ambiguity of “general paralysis.”^[ref] Modern medicine recognises the classical disease as a form of neurosyphilis, involving chronic injury to the brain. This causal diagnosis should be separated from the historical clinical label; it was not securely established by the wording of an 1864 examination. Syphilis serology, relevant cerebrospinal fluid findings and exclusion of alternative causes now help establish the diagnosis.^[ref]

Several mimics deserve explicit comparison. Mania can resemble the expansive mental phase, and depression or psychotic illness can resemble other presentations, but a sustained progressive combination of cognitive decline, characteristic speech disturbance and neurological signs argues for organic disease. Alcohol intoxication can produce tremor, slurred speech and an unsteady gait; an acute time course or improvement with clearance differs from progressive general paresis, although chronic alcohol-related disease may complicate the distinction. Other dementias, chronic cerebral vascular disease, tumours and some toxic or metabolic disorders can likewise combine cognitive and motor abnormalities.

A focal stroke generally gives a more abrupt and lateralised deficit; a series of strokes can produce a stepwise course. Parkinsonism can impair speech and gait but has a different predominant motor pattern. Tabes dorsalis can produce marked sensory ataxia, absent tendon reflexes and bladder disturbance with relatively preserved intellect; it can also coexist with paretic disease. The diagnosis rests on the pattern, course and corroborating investigation, not on grandiosity or a tremulous tongue alone.^[ref]