Tuesday, 26 July 2011


Published in Panorama

Childhood chickenpox - a precursor to Herpes Zoster

Seventy year old Sameer was plagued by itching and a tingling sensation around his right eye. Three to four days later he noticed red rash like structures in the region. His physician diagnosed him as suffering from Herpes Zoster, commonly called Shingles.

What is Zoster and who are the individuals prone to this disease? Dr.C.R.Chandrashekar, Specialist Dermatologist, Apollo Polyclinic explains that Zoster is a viral infection caused by the same virus that causes chickenpox. “The chickenpox virus remains dormant in certain nerve root cells of the body and when it reactivates in certain individuals, Zoster results. Some individuals may only be carriers of the chickenpox virus without having had an attack of it during childhood. In either case, the dormant virus, for whatever reason, becomes reactivated in the nerve root cells and travel along the nerve fibres and usually settle down in fairly isolated areas of the skin, usually on one side of the body.”

What are the symptoms of Zoster? In a typical case of Zoster, explains Dr.Chandrashekhar, the patient may have several days of itching, tingling, burning or pain in the affected region. This is followed by a red rash which evolves rapidly into vesicular eruptions. These lesions may be few in number and continue to form for 3-5 days. The vesicles become cloudy, dry and form scabs after a week or so, though the skin may take 2-4 weeks to return to normal. “In few individuals there may be no skin lesions and only the characteristic localized pain in the affected region may indicate Zoster,” clarifies Dr.Chandrashekhar.

Zoster most commonly occur on the trunk of the body and often appear as a band of blisters that wraps from the middle of the back around to the front of the chest or abdomen, following the course of the nerve, explains Dr.Chandrashekhar. “It can also appear on the face, arms or legs if nerves in these areas are involved. Branches of the trigeminal nerve may be involved in some cases, resulting in lesions appearing on the face, mouth, eye and tongue. In a condition called Ramsay Hunt Syndrome, the pain and vesicles appear in the external auditory canal which may result in the patient losing his sense of taste in a part of his tongue and also he may develop facial palsy on the same side as the affected nerve.”

Who are the people prone to Zoster? Dr.Chandrashekhar emphasizes, “Everyone who has had chickenpox or is a carrier of the virus, is a potential candidate for Zoster. However, those normally at risk of developing Zoster are the elderly and individuals with a weakened immunity. These include patients with malignancy, cancer, AIDS, HIV. In the immune-compromised patients, the incidence of Zoster is 8-fold compared to healthy individuals. These again are people who may have recurrent attacks of Zoster. While the elderly people above the age of 50 are the most likely victims, Zoster can also happen to young adults as young as 20 years old.”

Do the symptoms of Zoster mimic other diseases or ailments, thereby making diagnosis difficult? “We don’t do any fancy lab investigations for something that is clinically so clear much of the time,” reveals Dr.Chandrashekhar. The characteristic unilateral distribution of the eruptions and pain, should clinch the diagnosis most often. However, there can be nerve involvement alone, without skin lesions in some rare instances. Since there is no outward manifestation of Zoster, we have to go by the distribution of the pain and the degree of neuralgia. In these instances, the only thing is a high degree of suspicion of Zoster which helps diagnosis. Here the patients’ intelligence in describing the pain is important. Yet I would say it is still a tough call because you do get gall bladder and all kinds of pain which radiate alone one side of the trunk. Also, the pain could be mistaken for migraine since migraine can also be unilateral.

Is Zoster contagious? Shingles blisters carry the chickenpox virus which is contagious to people who have never had chickenpox, says Dr.Chandrashekhar. “There are of course young children who have not yet had chickenpox. In the very early stages of Zoster, there is some possibility of the viral transmission leading to chickenpox in these children. But it is unlikely to produce Zoster in another adult because Zoster is the result of a reactivation of one s own virus, not contracted from others; so only someone who has never had the virus is likely to get the problem and always, the first disease caused by this virus will be chickenpox, not Zoster.”

Once the blisters scab over, the Zoster patient is no longer contagious. However, it is better for certain categories of people to avoid physical contact with patients having Zoster blisters. These include pregnant women, newborns, individuals who have never had chickenpox and the immune compromised individuals.

How is Zoster treated? Antiviral therapy including drugs and cream, antibiotic creams to prevent blisters from becoming infected and turning into pustules, capsaicin cream a derivative of chillis and capsicum to treat the pain, oral painkillers, bed rest, anti-inflammatory drugs, sedatives to enable the patient to sleep and dressing with saline, form part of the treatment and pain management, says Dr.Chandrashekhar. “Apart from these, once we diagnose Zoster, we start the patients on a course of Vitamin B Complex (B1, B6 and B12) injections, five injections given every alternate day. Then onwards the treatment is with tablets for a few months, probably 2 3 months.”

Is it possible to prevent zoster with a diet rich, particularly, in Vitamin B group? “Very difficult,” opines Dr.Chandrashekhar. “If there is a drop in the patient s immune system for whatever reason, there is always the chance that he develops Zoster since this is a condition purely related to the reactivation of the virus. It is not as if you can target any particular individual as being prone to zoster and ask him to take nutritious food.”

What are the complications of zoster? “Post herpetic neuralgia or constant pain or pain for prolonged period of time in the affected region, even after the skin has healed, is the commonest complication of zoster. Hence, it is important for early diagnosis and treatment of the condition. Only 1-2% of patients can be stuck with post herpetic neuralgia, even after six months; 95% of patients become pain-free by six months and 50% become pain-free within 50 days.”

Though other complications can arise from untreated zoster, the chance of these happening are very rare since the condition is almost immediately diagnosed once medical help is sought, says Dr.Chandrashekhar. “However, an ophthalmologist or eye specialist should always be consulted when the lesions occur on the face, particularly near the eye since various eye problems can occur as a result of zoster.”

Elaborating on the eye involvement in zoster, Dr.Azim Siraj, Specialist Ophthalmologist, Prime Medical Centre, Dubai, explains, Blisters on the tip of the nose usually signal eye involvement. “Zoster can lead to conjunctivitis with the eyes typically looking red and watering. This might give some amount of purulent discharge. Red eye, watering from it and photophobia might be the next presenting symptoms. Then the white of the eye the sclera can also be involved in the presence of nodules and inflammation. The cornea itself may become involved. Small localized eruptions like ulcers may be present in the cornea. Since zoster affects the nerves, during the attack and sometimes even after the attack, it can result in the sensation in the cornea getting impaired, leading to inflammation of the iris and other eye structures.”

Continuing on the eye problems caused by zoster, Dr.Azim explains, “Zoster can also lead to Secondary Glaucoma, which is, increase in eye pressure within the eye. It can also affect the nerves supplying the muscles of the eye ball. In this case, the patient presents with paralysis so that the eyeball might not be able to move in certain directions. It can also lead to other nerve palsies like the facial nerve palsy, the 7th nerve palsy or other nerves which are directly related to the eyeball.”

“An inflammation can also occur in the retina and this is more so in immuno-compromised patients,” explains Dr.Azim. “In these individuals the virus attacks more violently and fulminantly. Retinitis can be a serious problem because in case of the fulminant type, it can cause decay of the retina and retinal detachment and probably subsequent loss of vision,” cautions Dr.Azim.

“Sometimes even the optic nerve can get inflamed, leading to a sudden drop in vision. The patient may complain of fading of colours, for instance, red looks like pink, and sudden drop in vision,” continues Dr. Azim.

Dr.Azim clarifies, “All this is the primary infection due to Zoster. In all cases where the immunity is down, other organisms can be present. For instance, a patient might have keratitis which is inflammation of the cornea; but there can be superadded infection from bacteria so that the patient can have secondary infection based on the immunity and hygiene of the patient.”

However, Dr.Azim is reassuring, “everyone of these conditions is treatable except when it gets to the fulminant type which just develops very fast, especially retinitis. But you must remember that Zoster can cause permanent loss in vision if not properly treated and on time.”

“Most importantly,” opines Dr.Azim, “any patient who starts getting Zoster, when it is extensive, should start looking out for immunity problems. Because there have been many cases where this can be the only presentation of HIV and the patient might not know he has HIV but a sudden onset of severe fulminant Zoster may indicate the presence of HIV.”

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