Swimming after meningitis

Vestibular impairments arising from meningitis can be hazardous in circumstances of impaired vision and proprioception, such as swimming.

CASE HISTORIES

Case 1

A woman of 63 had had bacterial meningitis in childhood, treated with intramuscular streptomycin. The sequelae included severe bilateral sensorineural hearing loss and poor balance, particularly when walking in the dark. Notably, she had been unable to learn to ride a bicycle. On two occasions, at ages 40 and 45 years, she had attempted to learn to swim, without success despite many lessons. At one point, when a frustrated swimming instructor had dragged her into the water to 'prove she could swim', she had become disoriented and unable to right herself in the water. Only during consultation to improve her hearing 18 years later did the reason for this become apparent. She proved to have bilateral vestibular hypofunction, and static posturography was grossly abnormal.

Case 2

Pneumococcal meningitis in a previously fit woman aged 30 resulted in weakness in her right leg, a dead right ear and a moderate to profound mixed hearing loss in her left ear, as well as impaired balance. She was warned of the possible risk of swimming and particularly advised never to swim unaccompanied. Subsequently, however, she found she was able to swim very well. 14 months later, while playing ball with her daughter in the shallow end of a swimming pool she jumped backwards, falling into the water. She immediately became disoriented and found she was unable to right herself, eventually coming to the surface. Vestibular testing demonstrated bilateral hypofunction, and static posturography was abnormal.

Box 1 Features of vestibular dysfunction

Delayed motor milestones in childhood

Difficulty learning to ride a bicycle or to skate

Impaired balance when visual and proprioceptive input reduced (e.g. swimming)

Poor balance in the dark (e.g. in cinemas, theatres)

Poor balance in circumstances of conflicting input (e.g. looking over a bridge, escalators)

Poor balance when walking on uneven surfaces

COMMENT

The maintenance of balance in man relies upon visual, vestibular and proprioceptive inputs which are integrated in the central nervous system with activity from other centres. With adequate visual and proprioceptive inputs, vestibular dysfunction can go unnoticed. However, in circumstances of reduced or conflicting inputs from the other two sensory modalities, the vestibular impairment can become evident with potentially devastating consequences. On this basis, swimming tests have been developed to evaluate the vestibular system in animal models.¹

Auditory and vestibular dysfunction secondary to meningitis has been well documented.^2,3 In most reported cases, vestibular impairment results from damage to the peripheral vestibular system. However, meningitis can also lead to central vestibular impairment. Streptomycin, which was used in case 1, is another well-known cause of vestibular disturbance.⁴

Box 1 outlines the clinical features of vestibular impairment. Previous reports have called for vestibular testing on all children post-meningitis.^5,6 Current guidelines in the UK advise that all children should have a hearing test within four weeks of discharge,⁷ but vestibular assessment is not routine. Survivors of meningitis (and, if children, their parents) need to know about the potential long-term dangers, particularly of swimming.