Clinical and hematological profile in a newborn cohort with hemoglobin SC

A systematic literature review of frequency of vaso-occlusive crises in sickle cell disease

BACKGROUND AND PURPOSE

Sickle cell disease (SCD) is a collection of rare inherited blood disorders affecting approximately 100,000 people in the U.S. and 20-25 million people globally. Individuals with SCD experience recurrent episodes of severe and unpredictable pain that are caused by vaso-occlusive crises (VOCs), a hallmark of the disease. VOCs are the primary cause of hospitalization in SCD, result in missed workdays and school days, and decrease quality of life (QoL). Although VOCs cause significant burden in the lives of individuals with SCD, there is no synthesis on the frequency of VOCs in the real world. This systematic literature review sought to identify literature describing the frequency of VOCs experienced by individuals with SCD in real-world settings.

METHODS

MEDLINE and 6 congresses were searched (date range: January 1, 2000 to June 30, 2020). Studies were reviewed independently by two researchers. Studies assessing frequency or prevalence of VOCs or VOC-related outcomes were included.

RESULTS

Of 1438 studies identified in the search, 52 met pre-specified inclusion and exclusion criteria. Reported frequency of VOCs varied widely ranging from a mean or median of 0 VOCs/year to 18.2 VOCs/year. The proportion of patients experiencing ≥ 3 VOCs/year ranged from 4 to 67% and the proportion of patients experiencing ≥ 5 VOCs/year ranged from 18 to 59%. Measures of VOC severity were limited, with 13 studies considering frequency of complicated VOCs and only 1 study reporting duration of VOC episodes.

CONCLUSIONS

This is the first study to systematically assess published evidence pertaining to VOCs in real-world settings. Reported VOC frequency in real-world settings varied widely, with a majority of studies only considering VOCs managed in an inpatient or outpatient setting. Studies that considered VOCs managed at home reported a higher frequency of VOCs, suggesting that many studies may underestimate the frequency of VOCs. This systematic literature review (SLR) highlights the need for consistent reporting of (1) self-reported VOCs, including those managed at home, (2) definitions of VOCs, (3) complicated VOCs, and (4) duration of VOC episodes in literature.

Prevalence of Bartonella spp. Infection in Patients with Sickle Cell Disease

Background: The inherent characteristics of the sickle cell disease (SCD), the most common genetic hematological disorder, increase the propensity of infections. Bartonella spp. are emerging and neglected bacteria. A large spectrum of clinical manifestations has been linked to bartonella bloodstream infection in the last two decades that can cause fatal outcomes, especially in immunodeficient patients. The goal of this study was to evaluate the prevalence of bartonella infection in SCD patients. Materials and Methods: We evaluated Bartonella spp. prevalence in 107 SCD patients. Blood samples and enrichment blood cultures were analyzed by molecular detection of Bartonella spp. DNA. Bartonella DNA was amplified using conventional genus-specific Bartonella PCR which amplifies the Intergenic Transcribed Spacer region and Bartonella henselae-specific nested PCR which amplifies the FtsZ gene. Positive patient DNAs were tested with ssrA conventional PCR. All amplicons were sequenced. Findings: Ten of 107 patients tested positive for B. henselae infection in at least one molecular test. All obtained amplicons were sequenced and similar to B. henselae sequences deposited in GenBank (accession number BX897699). Based on statistical results, bloodstream infection with B. henselae was not associated with animal contact or blood transfusions. Conclusion: We detected B. henselae DNA in 10 (9.3%) SCD studied patients. These patients were notified and treatment was offered to them.