The risks of the shingles vaccine
Patients need to be informed of the potential risk of this devastating complication
The “hellfire” of shingles is always best avoided. While the characteristic rosy-red rash caused by the herpes zoster virus usually clears in a few days, the stabbing, toothache-like pain of its after-effects, post-herpetic neuralgia, may persist for months.
Those who have had one such episode might naturally be inclined to have the shingles jab in anticipation of preventing another. It would, however, be prudent not to. For though it is certainly very effective in reducing the risk of shingles by two thirds, it can “reactivate” residual traces of the virus in the tissues.
This particularly applies to those in whom the original episode involved the scalp and eye (herpes zoster ophthalmicus), in whom the vaccine can induce an inflammatory reaction in the cornea and retina, resulting in visual impairment. “Patients need to be informed of the potential risk of this devastating complication,” observes ophthalmologist Bruce Jackson.
Similarly, parents need to be informed (though they are not) of the potential complications of the HPV vaccine Gardasil, routinely administered to adolescent girls for the past decade. The arguments over the payoff between its putative benefits in protecting against cervical cancer versus its adverse effects, rehearsed in this column earlier this year, are highlighted again by an overview of the relevant evidence published last month.
Neurologist Dr Manuel Martinezlavin of the University of Buffalo, writing in the journal Immunologic Research, summarises the findings of 10 studies from around the world. “The described symptom clusters are remarkably similar,” he writes, and include debilitating fatigue, headache, gut disturbances, fainting, weakness and memory impairment. Their onset soon after immunisation, suggestive of a causative role for the vaccine, is bolstered by their consistency, “independently confirmed by doctors in different places, circumstances and times”.
This merits further investigation – but, in the meantime, parents, rather than deferring to expert opinion of the vaccine’s safety, should prudently acquaint themselves with the contrary view.
Can’t feel my feet
The conundrum of the previously fit and healthy woman in her early 60s who developed numbness and a jellylike feeling in both feet after a cycling trip to France has elicited a couple of possible explanations. The “obvious” diagnosis of disturbed functioning of the sensory nerves (peripheral neuropathy) was ruled out by the findings of the relevant nerve conduction studies. So what else might be responsible?
“I had a similar problem exacerbated by walking and hiking,” writes one gentleman in whom it turned out to be due compression of the tibial nerve as it passes behind the bony prominence of the inner ankle into the foot. This tarsal tunnel is equivalent to carpal tunnel at the wrist, which causes pain and numbness in the hand, and may also require surgical decompression.
The further possibility would be disturbed functioning of the small nerves in the skin – a small fibre neuropathy – often experienced as a “wrinkle in sock” or “pebble in shoe” sensation. The nerve conduction studies being normal, the diagnosis requires a skin biopsy that reveals an abnormal appearance of those small nerve fibres. There is regrettably no specific treatment, though drugs such as amitriptyline may be of value, along with local anaesthetic (lidocaine) plasters.
Finally, combining two themes of recent columns – the hazards of the overzealous treatment of hypertension and the merits of complementary therapies – a Yorkshire reader commends acupuncture for lowering the blood pressure. She felt duty bound to come up with an alternative to drugs and, eventually, her family doctor agreed to a trial of the needling treatment. That was September last year, since when, together with a couple of booster sessions, her blood pressure remains in the recommended range.
There is, of course, no recognised physiological explanation why acupuncture should have this effect, which has been demonstrated in a formal clinical trial.
Be warned: the shingles vaccination can carry a risk of visual impairment