Clinical and Genetic Characterization of Cystinosis: Unmet Healthcare Needs in a Cohort Study from a Developing Country
Background
Cystinosis is a rare disease caused by CTNS gene defects. The main clinical presentations are nephropathic infantile cystinosis (NIC) and nephropathic juvenile cystinosis (NJC); both develop chronic kidney disease (CKD) and extrarenal complications. Opportune diagnosis and access to therapy are challenging in developing countries.
Methods
To describe the clinical and genetic profile in all cystinosis patients known to be diagnosed in Chile, we performed a retrospective review of the medical records of those patients diagnosed from 1994 to 2022. Age at diagnosis, glomerular filtration rate, metabolic variables, anthropometric values, access to treatment, outcomes, and genetic results were analyzed.
Results
Nine patients (8NIC/1NJC) were diagnosed. Patients with NIC had a median age of 16.5 (IQR 13-23) months at diagnosis, and two patients died during follow-up. Most of the patients started cysteamine therapy up to 5 months after diagnosis and reached CKD stages 3-4 within four years. During the follow-up, all but one of the NIC patients showed height for age Z-score values between -1.5 and -4.0. Two patients received kidney transplants, and one of them remains functional after 15 years. The single NJC was a 21-year-old female patient who received irregular cysteamine therapy and rapidly reached CKD stage 5. Genetic testing was positive in 7/7 cases, being del57kb the predominant variant (10/14 alleles).
Conclusions
Developing countries face many challenges in providing adequate healthcare. Our findings show clinical and diagnostic aspects to the medical and patient community that might contribute to the diagnostic approach and treatment access for cystinosis in Chile. Opportune genetic testing may facilitate early diagnosis that is known to be associated with a better prognosis.
DOI: 10.29245/2572-9411/2023/1.1208 View / Download PdfSurvival without Permanent Respiratory Support in a Patient with SMA Type 1 Treated with Nusinersen
Spinal muscular atrophy (SMA) is a rare, but severe disease, which is characterized by progressive muscular weakness resulting in permanent assisted ventilation before the age of 2. Supportive care used to be the only available treatment. However, relevant progress has been achieved with the approval of nusinersen (an antisense oligonucleotide modulating SMN2 splicing), which changed the disease outcome for many patients. Thus, management of SMA patients requires a multidisciplinary approach with pharmacological and non-pharmacological treatments to provide the necessary supportive care for symptom management, nutritional support and active rehabilitation to optimize muscle function. In this paper we aimed to report the first patient with type 1 SMA in the Latin America region that was able to get off the ventilator without a tracheostomy after an early treatment with nusinersen, continuing to date stable and with no need of ventilatory support.
DOI: 10.29245/2572-9411/2023/1.1207 View / Download Pdf