Old diseases now
Increase in tuberculosis and syphilis in UK presents new challenges for ophthalmic diagnosticians.
Diseases long thought to have been largely vanquished by modern medicine and improved living standards have been making a return in recent years. Among these are tuberculosis (TB) and syphilis, both of which have ocular manifestations that ophthalmologists must learn to recognise if patients are to receive appropriate treatment, said Professor Nicholas Jones FRCP, Clinical Director of Uveitis Service, Manchester Royal Eye Hospital.
Prof Jones noted that the incidence of TB in the UK decreased steadily from the early 20th Century, largely due to socioeconomic improvements. Mortality from the disease fell very steeply following the introduction of streptomycin in 1943. However, in the late 20th Century the incidence of the disease began to rise again, due primarily to immigration from countries where TB is endemic.
The incidence of TB in the UK is highest in London and Manchester where the incidence per 100,000 population is 26.2 and 25.8, respectively, compared to a 9.2 per 100,000 population in the UK overall. The incidence of TB-induced uveitis was likewise higher in these regions, Dr Jones said.
“Tuberculosis has not gone away and in our clinic it is a regular provider of patients to our uveitis service. It is a disease which must be treated differently from most cases of uveitis and therefore it needs to be spotted,” he stressed.
Prof Jones noted that TB-associated uveitis comprises a spectrum of inflammation that ranges from direct infection to TB-induced autoimmune infection, which does not necessarily require the presence of any mycobacteria in the eye.
“If I see an eye with uveitis and am confident that we are dealing with tuberculosis then I try and observe it first on anti-tuberculosis antibiotics alone for a couple of weeks to see whether the lesions will go away without steroid therapy, and that can be the final proof of our disease’s diagnosis,” he explained.
Prof Jones presented his experience at the Manchester Uveitis Clinic (MUC) where 182 TBU cases have been treated. All had ocular signs of TB and evidence of previous exposure. However, only half had a history of TB exposure or risk, only 20% had radiological evidence of previous TB such as Ghon focus lesions and mediastinal lymphadenopathy, and only 10% had evidence of concurrent active pulmonary or extrapulmonary TB.
As in most uveitis centres in the UK, the MUC uses the standard six-month regimen of treatment for TB-associated uveitis, starting with four antibiotics for two months, followed by two antibiotics for four months, with oral steroid as required. Six months after completing the antibiotic regimen, 80% of their patients are inflammation-free but of those, 40% are still receiving a topical and/or oral steroid.
“So we’re not talking complete success at all and there are many possible reasons for this including misdiagnosis. The second is the argument that that six-month treatment may not be adequate,” he said.
Syphilis is another disease that has been making a comeback in recent years, Prof Jones said. After a sharp decline following the introduction of antibiotics in the 1940s the incidence began to rise again in the 1960s, most likely as a result of the sexual liberation of those times, but then the incidence decreased again due the AIDS crisis.
Now with the introduction of AIDS medication that is much less toxic than the earlier antiviral agents and the added availability of HIV prophylaxis medication, together also with the wide use of social media for arranging casual liaisons, the incidence of syphilis is again on the rise, Dr Jones noted.
“Almost all patients with secondary syphilis which includes ocular involvement, present first to an ophthalmologist. Vigilance is therefore necessary to distinguish the condition from other forms of uveitis early in the course of the disease and provide effective treatment.
“The neurosyphilis antibiotic regime is curative, but prolonged oral steroid alone, or intraocular steroid, is blinding,” Dr Jones added.
Nicholas Jones: Nicholas.email@example.com