Correlates of Pulmonary Function in Children with Sickle Cell Disease and Elevated Fetal Hemoglobin

Cardiopulmonary changes in patients with sickle cell anemia: A systematic review

BACKGROUND

Given the high prevalence of cardiovascular and pulmonary abnormalities associated with sickle cell anemia (SCA), the clinical impact caused in addition to compromising the quality of life of patients and the overcharge that it represents to the public health system, this study systematized and evaluated scientific publications on pulmonary complications and cardiovascular diseases in sickle cell patients from 1920 to 2020. This compilation aims to provide knowledge for health professionals and managers in order to draw attention to the importance of chronic diseases in SCA patients and in addition to providing elements that provide improvements in management of useful resources that contribute to improve the quality and increase the life expectancy of these patients.

AIM

To systematically compile information about cardiopulmonary changes in patients with SCA.

METHODS

A systematic literature review was performed based on the PRISMA recom-mendation including scientific articles indexed in the Scientific Electronic Library Online databases of the United States National Library of Medicine and Biblioteca Virtual de Saúde. The search period was delimited between 1990 and 2020 and selected in Portuguese, English and Spanish. Three sets of descriptors were used for each database including research carried out with human beings. After reading the articles, those useful for this review were extracted using a collection instrument designed for this purpose.

RESULTS

The final selection included 27 studies. The year with the highest number of publications was 2016 with 5 studies (18.51%), followed by 2017 with 4 (14.81%). The type of study most carried out in the period was cohort 10 (37.03%) followed by cross-sectional and case-control with 8 studies in each (29.62%). Regarding the language of publication, the distribution was as follows: 25 (92.59%) in English, 1 (3.70%) in Spanish and 1 (3.70%) in Portuguese.

CONCLUSION

The findings of the present study suggest that cardiopulmonary alterations represent a serious clinical repercussion of SCA. Of the analyzed studies, the high occurrence of pulmonary hypertension, ventricular hypertrophy and diastolic dysfunction stands out as the main cardiopulmonary complications. In view of the increased survival in SCA, there is a need for surveillance and the development of strategies aimed at preserving the cardiopulmonary function and consequently improving the quality of life of these patients.

Troponin Elevation in Sickle Cell Disease

OBJECTIVE

Sickle cell disease is associated with cardiovascular abnormalities. Troponin is not typically measured in this population, and thus the significance of abnormal levels of troponin is unknown. We wanted to evaluate the use of troponin and factors that predispose troponin elevation in patients admitted with sickle cell pain crisis (SCPC).

METHODS

We reviewed data of consecutive patients admitted to a tertiary care hospital between 2006 and 2011 with a diagnosis of SCPC. Subjects with elevated troponin (ET) (troponin I >0.04 ng/mL) were compared with those with normal troponin (NT) for demographics, risk factors, presence of echocardiography-derived tricuspid regurgitant jet velocity (TRV) ≥3 m/s suggesting pulmonary hypertension, and laboratory tests. The Mann-Whitney U test was used to compare groups.

RESULTS

Two hundred eighty-three of 724 patients admitted with SCPC had chest pain. Troponin I was measured in 63 patients: 51 had NT and 12 had ET ranging from 0.06 to 3.42 ng/ml. ET was associated lower hemoglobin (p = 0.02), lower hematocrit (p = 0.02), lower platelet number (p < 0.001), higher LDH (p = 0.012), higher AST levels (p = 0.004), higher bilirubin levels (p = 0.006), and TRV ≥3 m/s (p = 0.028).

CONCLUSIONS

Troponin was measured in <10% of patients with SCPC, and 1 out of 5 of them had ET. Troponin elevation was not associated with traditional cardiovascular risk factors but was associated with lower hematocrit, elevated LDH, bilirubin levels, and TRV ≥3 m/s.

Acute chest syndrome in sickle cell anaemia: higher serum levels of interleukin-8 and highly sensitive C-reactive proteins are associated with impaired lung function

BACKGROUND

Sickle cell anaemia (SCA) is a chronic inflammatory disorder with multiple organ manifestations including acute and long-term pulmonary dysfunction.

AIMS/OBJECTIVES

To assess lung function of children with SCA and determine the possible role of acute chest syndrome (ACS), serum inflammatory cytokines, highly sensitive C-reactive protein (hs-CRP), leucocytes and 25-hydroxyvitamin D on the development of impaired lung function.

SUBJECTS AND METHODS

Lung function of 76 children with SCA was determined by spirometer and classified into normal or impaired. Sociodemographic, clinical, haematological, biochemical and immunological data of the two groups were compared by univariate and multivariate analyses.

RESULTS

Fifty (65.8%) patients had impaired lung function, comprising of 30.3%, 3.9% and 31.6% with restrictive, obstructive and mixed disease patterns, respectively. Children with previous ACS were 3.6 times more likely to have impaired lung function than those without ACS (82.1% vs 56.3%, p = 0.02, OR 3.6, 95% CI 1.2-10.8). Interleukin (IL)-8 and hs-CRP were significantly higher in patients with impaired lung function (p = 0.02 and <0.001, respectively). Using logistic regression, previous ACS (OR 5.8, 95% CI 1.1-5.8, p = 0.03) and higher serum IL-8 levels (OR 3.0, 95% CI 1.0-8.0, p = 0.02) independently predicted the presence of abnormal lung function.

CONCLUSIONS

Lung dysfunction, predominantly restrictive pattern, is common in SCA and is associated with previous ACS and alterations in immunological markers, especially serum IL-8 and hs-CRP.

ABBREVIATIONS

ACS: acute chest syndrome; CBT: chronic blood transfusion; ELISA: enzyme-linked immunosorbent assay; FEV₁: forced expiratory volume in 1 s; FVC: forced vital capacity; HPLC: high-density liquid chromatography; hs-CRP: highly sensitive C-reactive proteins; HU: hydroxyurea; IL: Interleukin; PEFR: peak expiratory flow rate; SEM: standard error of the mean; TLC: total lung capacity; 25-OHD: 25-hydroxyvitamin D; VOC: vaso-occlusive crisis; WGH: Wesley Guild Hospital.