SITTING in her dad's car outside Liffey Valley shopping centre, Alison Walsh felt a pang of jealousy as she watched a girl her age walk past.
"She was carrying her shopping bags and had Starbucks in her other hand," she remembers. "It was such a simple thing but I remember looking out the window thinking 'I wish that was me', just living a normal life."
But it was the end of 2011 and Alison's life was anything but normal. She had lost the ability to walk and was suffering terrible headaches. She couldn't sleep, found it hard to eat and had couldn't stop her hands from shaking.
Her symptoms were so severe she could no longer go to work at the Blood Transfusion Service where she was employed as a medical scientist, and was now largely bedridden.
Most terrifying of all -- no one seemed to know what was happening to her.
It all began in 2008 with a series of seemingly innocuous problems.
"I just started feeling a bit rubbishy. I felt tired and run down and I wasn't sleeping well," explains Alison (35) from Enfield, Co Meath.
"At first I thought it was stress related. I was getting over a bereavement -- my uncle had been killed in a road accident and his death had been a huge shock, I thought it could be that."
Because the lymph nodes in her armpit were swollen, Alison's GP scheduled a biopsy, which revealed sarcoidosis of the lymph nodes.
The condition, which worldwide affects between 10 and 20 people in every 100,000 of the population, causes small lumps of inflamed cells to collect in the organ tissue affecting the performance of that organ.
It's commonly found in the lungs or lymph nodes, and initially doctors were pleased with Alison's diagnosis.
"I was put on steroids and it was expected I'd make a full recovery but instead I started developing other symptoms. I had night sweats, a dry cough and a terrible thirst all the time.
"Then I began getting horrendous headaches and vomiting sporadically. My walking became seriously compromised. It started with jerks in my legs at night, then my balance went."
Alison had been born with spina bifida and, although she was largely healthy and able to walk, it was initially suspected that she might have been suffering from hydrocephalus, also known as 'water on the brain', a condition closely associated with spina bifida and consistent with many of her symptoms, but this wasn't the problem.
In June 2011 she was diagnosed with sarcoidosis of the bones -- a rare condition usually detected in West Indian populations -- and later sarcoidosis of the skin was also detected.
But by September 2011 Alison was unable to walk and with inconclusive CT and MRI scans, she was discharged from hospital with a letter saying that while she was 'clearly symptomatic' doctors didn't feel there was a neurosurgical problem.
"By this stage I was six and a half stone and could do nothing for myself," explains Alison. "My husband, Gary, was looking after me as if I were someone in my 90s with dementia. He had to clean up my vomit, put me in the shower and put me on the toilet.
"At a time in our lives when we should have had prams and baby toys to trip over in the house, he was caring for me and tripping over my walking aides."
With Gary, a hotel personnel manager, out at work most of the day Alison made the difficult decision to temporarily move back to her mum and dad's home where her 58-year-old father, Pat, came home early from work to care for her. "I couldn't do anything. I was so anxious I couldn't sleep or read, I couldn't even roll over in bed," she explains.
"One day I spent three hours trapped between the bed and the wall just crying. Everything was a struggle and I didn't know if I was ever going to get better."
Her GP referred her to another neurologist and on December 31 another MRI scan was taken, this time using contrast dye to get a clearer picture of the tissue being examined.
On the second Tuesday of January 2012, she was admitted to St James's where she was diagnosed with the rare neurological disease neurosarcoidosis. The condition is typically only seen in around 5pc of people already suffering one form of sarcoidosis and can be life threatening. It was the inflammation in Alison's brain and spinal chord, detected by the contrast dye scan, that was causing the loss of movement in her legs, dizziness and nausea.
She was immediately put on a heavy dose of steroids to reduce tissue inflammation and given a double dose of Infleximab, a drug she was already on, to calm her immune system that had been sent into overdrive by her illness. "When I finally got the diagnosis I just felt drained," says Alison. "I couldn't even cry. After so much stress and worry, I felt completely emotionless. I lost the ability to talk at points which doctors put down to the stress I'd been under"
After six months on steroids and Infleximab, the disease went into remission, but the scarring damage to her nervous system meant it was a struggle to regain her mobility.
She signed up for physiotherapy sessions with Pat Byrne of the Muscle Clinic Clontarf using an anti-gravity treadmill to build up strength and eventually, in May last year, she felt strong enough to move back home.
"The first time I took a couple of steps, my dad said it was like watching me as a baby, I was so wobbly."
Now back to her original weight of eight stone 10, Alison hopes to return to work but she'll be on medication the rest of her life and has struggled financially after repeatedly being refused a medical card.
"I'm not a saint, I still get times when I'm down about everything I went through but there are positives too," she admits. "I'm more confident now and I challenge myself to do more now physically."
She adds: "Most importantly, I want to use my experience to make other people aware of sarcoidosis. It can be difficult to detect and starts with a lot of vague symptoms that many people would just brush off, but it's important not to ignore them."
Neurosarcoidosis: the facts
What is it?
SARCOIDOSIS is a multi-organ disease where tiny clumps of abnormal, inflamed tissue (granulomas) form, affecting that organ's performance. Neurosarcoidosis is when the disease affects the nervous system causing muscle weakness and often affecting the area of the brain dealing with sleep and stress response.
Who gets it?
Sarcoidosis is prevalent in Ireland and affects one or two in 1,500 people. It often occurs between the ages of 20 and 40 with women slightly more likely to develop it, and risk increasing if there's a family history of the disease. Neurosarcoidosis is very rare -- only present in approximately 5pc of sarcoidosis cases worldwide.
It is not known what causes sarcoidosis.
There is no established cure for neurosarcoidosis. Treatment focuses on easing symptoms using immunosuppresants to control the disease and steroids to reduce inflammation.
Symptoms vary as any part of the nervous system can be affected, but they may include fatigue, excessive thirst, dizziness, headaches, loss of vision or sense of smell, speech impairment, loss of movement in any body part and nausea.
For more information about the condition visit the Irish Sarcoidosis Support Network website: www.isarc.ie