When primary school pupil Denisse Kong, 11, first complained of aches around her ankles and heels more than two years ago, her parents dismissed it as growing pains.
"We even bought her a bigger pair of shoes," said her mother, Ms Anna Seah, an allied health professional.
However, the aches did not go away. Denisse started to miss physical education lessons because she felt very tired.
Then, she experienced stiffness in other parts of her body. "She started to walk slowly. We thought she was just tired and I'd help her with her schoolbag," said Ms Seah, 40.
Things became clearer after Denisse was hospitalised for a prolonged high fever.
"She didn't complain much about the joint pains, but her mother saw that she was moving a lot slower and she couldn't put on her shoes because her feet were so swollen," said Dr Elizabeth Ang, a consultant at the division of paediatric allergy, immunology and rheumatology, National University Hospital (NUH).
If it goes undetected or if you delay treatment for years, the child can become permanently crippled or disabled.
ASSOCIATE PROFESSOR THASCHAWEE ARKACHAISRI from KK Women's and Children's Hospital.
"She had so many joints that were painful and swollen that it was hard for her to move, even in bed."
Denisse was diagnosed with juvenile idiopathic arthritis (JIA), a condition in which kids experience joint pain, stiffness and swelling.
The number of JIA cases here has slowly risen in the past eight years.
At KK Women's and Children's Hospital, about 40 to 50 new young patients have emerged every year since 2013, compared with 30 to 40 each year from 2009 to 2012, said Associate Professor Thaschawee Arkachaisri, its senior consultant and head of rheumatology and immunology service, department of paediatric subspecialities.
Prof Thaschawee said there are about 400 children with JIA in Singapore, being treated at KKH or elsewhere. NUH sees one to two new cases a month. He attributed the rise to increased awareness among paediatricians and the public, though awareness remains very low.
"The awareness of childhood- onset arthritis is lacking not only among the general public, but also among healthcare professionals. This may lead to a delay in diagnosis and treatment," he said.
Joint inflammation can be treated and children affected by it can go on to lead normal lives, he said. "What I want to stress about this disease is that if it goes undetected or if you delay treatment for years, the child can become permanently crippled or disabled."
Not only does arthritis result in pain and limitation in movement, but it also causes long-term bone and joint damage, he said. Juvenile arthritis can also cause limb-length discrepancy in children, he added.
When Prof Thaschawee first arrived in Singapore about six years ago from the United States, where he had worked, he saw a few children who had irreversible joint deformities as a result of JIA that was left untreated for several years.
As arthritis causes pain and swelling, the child would not want to use the joint or joints that hurt. If the condition goes undetected and the joint is not used, the bone and muscle near it will become smaller and weaker.
Most patients achieve normal joint movement after treatment, said Dr Liew Woei Kang, consultant paediatrician at SBCC Baby & Child Clinic, Gleneagles Medical Centre.
JIA is the most common form of chronic arthritis in kids. It occurs in children aged 16 and below and has seven sub-types, including enthesitis-related arthritis, which affects more boys than girls and is the most common form of JIA here.
Dr Ooi Pei Ling, an associate consultant at NUH's division of paediatric allergy, immunology and rheu- matology, said JIA is an autoimmune condition where the body's immune system mistakenly attacks healthy cells in the joints. Doctors do not fully understand why this happens.
But with early detection, diagnosis and treatment, children with JIA can grow and develop normally, said Prof Thaschawee. They do not look any different from other kids once the disease is under control.
Thanks to a new group of drugs called biologics, doctors can now control close to 100 per cent of JIA. In the past, patients may not always experience normal growth and joint function, even with early treatment, said Prof Thaschawee.
These drugs can cost around $2,000 a month, but subsidies are available from the Government and the National Arthritis Foundation.
"Once the arthritis is in remission for about six months, we will wean the patient off the medication before eventually stopping it," he said.
However, JIA may recur as it is a chronic disease.
Studies have shown that the earlier the arthritis goes into remission with treatment, the less likely it will recur, said Dr Ang.
For Denisse, life has greatly improved. In hospital about two years ago, she was "like a wooden block", but she could sit up and turn her head after the first treatment, said her mother.
Denisse is now growing well and has resumed playing badminton with her older sister, she said.
Dr Ang said it has been a difficult journey for Denisse, who has systemic JIA, the most severe form of the disease. It affects the whole body and not just the joints.
She became completely well only after starting daily injections. She now injects herself with the drugs once every four days. "I take a deep breath and I just jab," she said.