LAUSR

To the Editor: The diagnosis of acute chest syndrome (ACS) relies on the presence of an infiltrate on chest radiograph in a patient with sickle cell disease (SCD) along with 2 or more of fever, wheezing, tachypnea, cough, or chest pain.1 It can occur during childhood and can lead to death. We evaluated the current hospitalization burden of ACS in patients with SCD between ages 0 and 20 years inclusive. The 2016 Kids’ Inpatient Database (KID) is provided by the Healthcare Cost and Utilization Project (HCUP) and Agency for Healthcare Research and Quality.2,3 The International Classification of Diseases, Tenth Revision, Clinical Modification (ICD10-CM) code for “Hb-SS disease with acute chest syndrome” (D5701) was used.4 The data were analyzed using SPSS 20, and a P-value <0.05 was considered as statistically significant. The 2016 KID contained 6,266,285 weighted admissions across the United States. A total of 4230 cases of ACS were reported in patients with SCD. Overall, 2312 (54.7%) were males and 1918 (45.3%) were females (P<0.05). Moreover, 3326 (90.4%) cases were seen in African Americans (P<0.05), and the condition was more common in the southern part of the United States with 2249 admissions (53.2%; P< 0.05). Overall, 70.7% of the admissions (2985 cases) were covered by Medicaid (P< 0.05), and 1892 (45.2%) came from households with a median income within the 0th to 25th percentile. The mean age of patients with SCD in our study who presented with ACS was 10.86, a median of 11.00, and the lower quartile range was 6.00, whereas the upper quartile range was 16.00 (P< 0.05). The mean length of stay (LOS) was found to be 4.93 days, and the median LOS was 4.00 (interquartile range: 2.00 to 6.00, B: 0.945, 95% confidence interval: 0.667 to 1.223, P< 0.05). The mean hospital charge was $41312.32 (median: $26643.00, interquartile range: 15799.00 to 48990.84, B: 12688.632, 95% confidence interval: 8972.682 to 16404.582, P< 0.05), whereas the total hospital charges of Hb-SS patients with ACS were $172,464,697. The disease was more common in children aged 7 years (330 cases, 7.8%). Our study provides an update on the most recent burden of ACS in patients with sickle cell in the United States. However, the median LOS of the 2016 data correlates with the 2009 and 2012 analysis previously done,5 and the mean LOS has shown a slight decline.6 A rise in the median hospital charges was also noted, as it increased from $22,631 per admission in 2012 to $26,643 in 2016. The improvement in mean LOS and higher charges can be attributed to several changes in Medicaid and the Affordable Care Act to accommodate patients with SCD, which has led to easier access to treatment and improved quality of patient care over the past years.6 Similar patterns in patient characteristics, for example, higher male to female ratio, higher black ratio, and higher prevalence in the southern part of the United States, have previously been reported. Further preventive measures, such as improved vaccination protocols, prophylactic antibiotic administration aimed at lowering the risk of infections leading to ACS, and avoidance of tobacco exposure should be encouraged in those population groups.7 The introduction of a new code for “Hb-SS disease with acute chest syndrome” in ICD-10 has improved the accuracy in identifying cases of ACS in patients with SCD from the 2016 KID. However, there are some shortcomings with HCUP data, as we rely on reported data. ACS can be underdiagnosed and mislabeled as less severe conditions such as bronchiolitis and pneumonia.5 This can be resolved by encouraging physicians to monitor the rate of respiratory decline in helping with their diagnosis of ACS.8 We believe that prospective hospitalbased observational studies can help confirm these findings and eventually provide potential improvements in the management of ACS (Table 1).