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Introduction: In acquired hemophilia A (AHA), the body produces auto-antibodies against Factor VIII. Although AHA is rare, with an incidence of 1.5 patients/1 million population/year, there is a strong association with human immunodeficiency virus (HIV) infection. The accurate interpretation of screening coagulation tests is critical to identify patients with AHA, as the mortality rate secondary to bleeding is high. Methods: This was a retrospective case series which included all newly diagnosed AHA patients that were referred to Hemophilia care unit at King Edward VIII Hospital, Durban, South Africa from January 2011 to December 2021. The clinical presentation and laboratory results were documented. Results: Five patients were included in this case series. All patients were females aged between 28 and 64 years of age and they were HIV seropositive. They presented with spontaneous cutaneous and intramuscular bleeding. Four patients were virologically suppressed on anti-retroviral therapy, and no patient had a family history of congenital bleeding diathesis. Laboratory investigations confirmed AHA with high Factor VIII inhibitor titers, which ranged from 41 to 900 Bethesda Units (BU). All patients were managed with bypassing agents and oral corticosteroids. The monitoring of patients after the initiation of treatment was difficult as they all defaulted treatment. Conclusion: In view of the prevalence of HIV in sub-Saharan Africa, there is a possibility that AHA is under-diagnosed in our setting. The clinician and the laboratory have a combined critical role in identifying patients with AHA as the investigation of a prolonged APTT is mandatory. There are challenges in managing AHA patients in a resource-constrained setting.

Background: Automated haematology analysers such as the Sysmex XN-3000 (Sysmex Corporation, Kobe, Japan) utilise white blood cell (WBC) flags to identify quantitative and qualitative abnormalities. Owing to clinical and biological factors, the sensitivity and specificity of the flags vary when compared to microscopy, the gold-standard method for assessing peripheral blood smear (PBS) morphology. Objective: This study assessed the performance of the Sysmex XN-3000 haematology analyser in comparison to PBS microscopy for the detection of WBC abnormalities. Methods: We collected 250 random full blood count samples from the haematology laboratory at Inkosi Albert Luthuli Central Hospital, Durban, KwaZulu-Natal, South Africa, from March 2022 to April 2022. The performance of the automated WBC flags of the Sysmex XN-3000 was assessed in comparison to PBS microscopy, and the impact of established clinical variables on the performance of the flags was determined. Results: The sensitivity of the ‘blast’ flag was 96.3%, and the specificity was 84.9%. The efficiency of the flag was adversely impacted by low white cell counts ( 1.5 × 109/L; p 0.001), chemotherapy (p = 0.002), malignancy (p = 0.02), and infection (p = 0.02). The ‘abnormal lymphocyte’ flag demonstrated a sensitivity of 90% and a specificity of 96.2%, and its performance was adversely impacted by chemotherapy exposure (p = 0.03). Three cases (1.2%) erroneously flagged as ‘monocytosis’ demonstrated blasts on microscopy. Conclusion: In our setting, PBS microscopy remains necessary to confirm blasts, abnormal lymphocytes, and monocytosis in patients with malignancy, current chemotherapy exposure, low white cell counts, and infection. What this study adds: This study adds evidence that PBS morphology remains the gold standard for confirming WBC abnormalities in patients with a history of malignancy, chemotherapy, and leucopenia.

Background: The recommendation for coagulation blood samples is to centrifuge at 4000 revolutions per minute (rpm) for 15 min to produce platelet-poor plasma before analysis. Rapid centrifugation, defined as centrifuging samples at higher speeds for shorter durations, could potentially reduce turn-around times (TAT), provided sample integrity is maintained. Objective: This study assessed the impact of rapid centrifugation on routine coagulation assay results. Methods: Blood samples were collected from volunteers at Inkosi Albert Luthuli Central Hospital and King Edward VIII Hospital, Durban, KwaZulu-Natal, South Africa, from September to November 2021. Samples were centrifuged using Method A, the current standard (4000 rpm/15 min), Method B (4000 rpm/10 min), Method C (5000 rpm/10 min) and Method D (5000 rpm/5 min). Platelet count, prothrombin time, activated partial thromboplastin time, thrombin time (TT), fibrinogen and D-dimer levels were analysed and results from Methods B, C and D compared to reference Method A. Results: Platelet-poor plasma was obtained from all samples (n = 60) using Methods A and B, and from 33/60 (55%) samples using Methods C and D. Differences between Method A and Methods C and D for normal prothrombin time, normal D-dimer and abnormal TT results were statistically significant. Prothrombin time results correlated strongly across all methods, while TT and D-dimer results correlated poorly. Activated partial thromboplastin time and fibrinogen results showed no significant differences across all methods. Conclusion: Rapid centrifugation at 4000 rpm/10 min (Method B) showed results consistent with the reference method. This method could potentially reduce the overall TAT for routine coagulation assays.

ackground:Minimal residual disease (MRD) detection has been shown to be the best prognostic factor in B-acute lymphoblastic leukaemia (B-ALL). Multicolour flow cytometry (FCM) and specific molecular aberrations (MOL) are the classic techniques used to assess MRD. The former is faster and less costly. Aim: This study compares morphology and FCM to MOL in detecting MRD. Setting: The study was conducted at Inkosi Albert Luthuli Central Hospital (IALCH). Methods: A retrospective review of children with B-ALL managed at IALCH from January 2013 to January 2018 was conducted. Multicolour flow cytometry was performed using Euroflow® panels. Molecular aberrations looked at common cytogenetic markers. Presentation and post-induction morphology (May–Grunwald Giemsa stain), FCM and MOL data for MRD were analysed. Results: Eleven patients were excluded (6-demised, 5-incomplete records), leaving 64 to be analysed (54% female, median age 5 years). Five post-induction aspirates were unsuitable but the rest (92%) were in morphological remission. At diagnosis and post-induction, 62 (95%) and 61 (94%) children, respectively, had FCM performed. A positive MOL result was found in 39 (60%) patients. MOL turn-around times (TATs) averaged 14 days compared with those of FCM’s average of 3 days. MRD was found in 9 patients (FCM) and 7 patients (MOL). Of these patients, 4 had a good correlation between the two and 2 patients with negative FCM had positive MOL MRD post-induction. Conclusion: Morphology is insensitive in MRD assessment. FCM correlated well with molecular MRD and has the shortest turn-around time. FCM has major benefit in the 40% of patients with negative MOL. It can also be safely used to guide treatment escalation in those patients awaiting molecular results.

Background: Referral of samples for the work-up of haematological disorders from remote laboratories can result in a delay in analysis. Objective: The stability of the full blood count (FBC), differential count (DIFF), reticulocyte and peripheral blood smear (PBS) morphology during extended storage was evaluated. Methods: Forty blood samples stored in ethylenediaminetetraacetic acid (EDTA) were analysed on an ADVIA® 120 haematology analyser. The samples (25% abnormal; 75% normal) were stored at room temperature (RT) and at 4 °C – 8 °C. Analysis of samples stored at RT was performed every 12 hours for two days. Analysis of samples stored at 4 °C – 8 °C was performed at 12 hours and subsequently every 24 hours for seven days. Results: FBC parameters (red cell count, haemoglobin) and DIFF parameters (percentages of basophils, lymphocytes and monocytes) were stable for at least 48 hours when stored at RT. Platelets were only stable for 12 hours and the white cell count was stable for 36 hours when stored at RT. Storing samples at 4 °C – 8 °C significantly increased the stability of most parameters, in particular, mean cell volume and percentage of reticulocytes. However, DIFF parameters were associated with lower stability at 4 °C – 8 °C. PBS morphology was compromised prior to 12 hours whether stored at RT or at 4 °C – 8 °C. Conclusion: This study provides evidence that blood samples stored in EDTA at 4 °C – 8 °C for seven days are suitable for testing on the ADVIA® 120 analyser for the FBC and percentage of reticulocyte parameters. However, storage at 4 °C – 8 °C is not a solution for samples referred for DIFF and PBS morphology review.