Hot topics in coagulation testing: Important considerations for testing children for bleeding/thrombotic disorders

The accurate use and interpretation of diagnostic investigations are essential for safe and effective patient care. Appropriate application and interpretation of coagulation testing can be challenging, and many controversies exist relating to the standardization of testing procedures, the application of relevant tests to different patient populations and the interpretation of test results. We present a list of the most prominent controversies in coagulation testing and have selected three specific examples (age‐appropriate reference ranges, therapeutic anticoagulation monitoring and tests of thrombin generation) for closer discussion, highlighting examples with a paediatric framework. We discuss the limitations of discrete age‐partitioned reference intervals, given the established principle of developmental haemostasis; the difficulties in establishing normative data across different laboratories; important pre‐analytical variables affecting coagulation testing; the challenges in interpreting APTT and anti‐Xa assays for monitoring unfractionated heparin therapy in different clinical situations; and the limitations in interpreting tests of thrombin generation due to current available thrombin‐specific substrates and the complicating factor of variable alpha2‐macroglobulin levels. These controversies are demonstrated using paediatric examples, but raise important implications for coagulation testing in patients of all ages and highlight the pressing need for further research in these areas.     

Molecular and Serological Diversity of Neisseria meningitidis Carrier Strains Isolated from Italian Students Aged 14 to 22 Years

Neisseria meningitidis is an obligate human commensal that commonly colonizes the oropharyngeal mucosa. Carriage is age dependent and very common in young adults. The relationships between carriage and invasive disease are not completely understood. In this work, we performed a longitudinal carrier study in adolescents and young adults (173 subjects). Overall, 32 subjects (18.5%) had results that were positive for meningococcal carriage in at least one visit (average monthly carriage rate, 12.1%). Only five subjects tested positive at all four visits. All meningococcal isolates were characterized by molecular and serological techniques. Multilocus sequence typing, PorA typing, and sequencing of the 4CMenB vaccine antigens were used to assess strain diversity. The majority of positive subjects were colonized by capsule null (34.4%) and capsular group B strains (28.1%), accounting for 23.5% and 29.4% of the total number of isolates, respectively. The fHbp and nhba genes were present in all isolates, while the nadA gene was present in 5% of the isolates. The genetic variability of the 4CMenB vaccine antigens in this collection was relatively high compared with that of other disease-causing strain panels. Indications about the persistence of the carriage state were limited to the time span of the study. All strains isolated from the same subject were identical or cumulated minor changes over time. The expression levels and antigenicities of the 4CMenB vaccine antigens in each strain were analyzed by the meningococcal antigen typing system (MATS), which revealed that expression can change over time in the same individual. Future analysis of antigen variability and expression in carrier strains after the introduction of the MenB vaccine will allow for a definition of its impact on nasopharyngeal/oropharyngeal carriage.     

Craniofacial bone atrophy in Parry Romberg syndrome demonstrated using a Bayesian hierarchical model

PurposeParry Romberg syndrome (PRS) is a condition characterized by progressive hemifacial atrophy, predominantly affecting the soft tissues. Associated bone retraction is a common clinical feature of PRS but has never been assessed. Here we used 3D imaging and Bayesian statistics in order to demonstrate and quantify bone atrophy in PRS.Materials and methodsTen non-operated patients with PRS (4/10 males) and 12 age-matched controls (7/12 males) were included into the study. The average age at CT-scan was 9.67 ± 4.13 years for PRS patients and 12.5 ± 4.37 years for controls. Soft and hard tissue atrophy levels were quantified using computed tomography scans, based on the distances between surfaces of the affected side and the non-affected contralateral side, both for the skin and the bone. We used a hierarchical Bayesian model with clinical priors in order to assess the relationship between hard and soft tissue atrophies.ResultsPRS patients had significant hard tissue atrophy, and atrophy extents were similar for soft and hard tissues. There was a trend for a correlation between the extent of hard tissue retraction and the extent of soft tissue retraction, and we could not demonstrate that the relationship between hard and soft tissue retractions was different in PRS and controls.ConclusionOur results indicated that bone atrophy was most probably a primary process rather than a phenomenon secondary to soft tissue retraction. We have provided the first assessment of bone atrophy in PRS patients using Bayesian statistics.     

Refractory Intracranial Hypertension in Posterior Reversible Encephalopathy Syndrome

Introduction

Posterior reversible encephalopathy syndrome (PRES) is a largely reversible disease with long-term favorable outcome. A minority of patients, however, may develop progressive cerebral edema and ischemia resulting in severe disability or death. We report a case of severe intracranial hypertension associated with PRES that was successfully treated according to intracranial pressure (ICP)- and cerebral perfusion pressure (CPP)-driven therapy.

Methods

Case report.

Results

A 42-year-old woman underwent bilateral lung transplantation for severe bronchiectasis. Her immunosuppressive regimen consisted of azathioprine, prednisone, and tacrolimus. She acutely developed an aggressive form of PRES that rapidly resulted in severe refractory intracranial hypertension despite discontinuation of potentially causative medications and adequate supportive therapy. Accordingly, second-tier therapies, including barbiturate infusion, were instituted and immunosuppression was switched to anti-thymocyte globulin followed by mycophenolate mofetil. Within 10 h of barbiturate administration, ICP dropped to 20 mmHg. Thiopental was administered for two days and then rapidly tapered because of severe urosepsis. Six months after discharge from the intensive care unit the patient returned to near-normal life, her only complaint being short-term amnesia.

Conclusions

The decision to undertake ICP monitoring in medical conditions in which no clear recommendations exist greatly relies on physicians’ judgment. This case suggests that ICP monitoring may be considered in the setting of acute PRES among selected patients, when severe intracranial hypertension is suspected, provided that a multidisciplinary team of neurocritical care specialists is readily available.     

Degree of mucositis and duration of neutropenia are the major risk factors for early post-transplant febrile neutropenia and severe bacterial infections after reduced-intensity conditioning

Background and objectives: Whether the intensity of the conditioning regimen affects febrile neutropenia (FN) and severe bacterial infections (SBIs) is not well established. We analyzed the risk factors (RFs) for the development of FN and SBI in the first 100 d post‐transplant in 195 consecutive adult recipients of a reduced‐intensity conditioning allogeneic hematopoietic stem cell transplantation (RIC‐allo). Materials and methods: The RIC regimens consisted of fludarabine plus melphalan (62%) or busulphan (38%) (FluMel or FluBu). SBIs include pneumonia, urinary tract infections, and bacteremia. Results: FN occurred in 141 patients (72%), always in the first 30 d post‐allo‐RIC. However, a SBI occurred in only 27 patients (14%) during this early post‐transplant period (P < 0.02) and NCI CTC grade III–IV mucosal damage in the first 10 d post‐transplantation (P = 0.03). RFs identified to SBI by multivariate analysis included corticosteroid therapy before day +100 (P < 0.01), mycophenolate mofetil‐based graft‐versus‐host disease (GVHD) prophylaxis (P < 0.01), and previous SBI before day +30 (P < 0.01). The rate of SBI from day +30 to +100 varied according to the number of RFs; thus, the rate of SBI was 1% in patients without any RF, 17% in patients with one RF, 29% with one RFs, and 53% in those with all three RFs. Conclusions: After an RIC‐allo, FN and early SBI occurred mostly in patients with severe mucositis and early‐onset neutropenia, while postengraftment high‐dose steroid therapy for acute GVHD was the major RF.     

Locoregional recurrence in patients with HER2 positive breast cancer

Literature shows that HER2/neu positive breast cancer cells are more sensitive to radiation-induced apoptosis by targeting the epidermal growth factor receptor family tyrosine kinase. We selected 466 patients with pT1-2 HER2/neu positive tumors who received adjuvant trastuzumab for primary invasive breast cancer. Patients were divided into three groups [Quadrantectomy followed by conventional radiotherapy vs Quadrantectomy followed by Intra-operative radiotherapy with electrons vs Mastectomy without radiotherapy]. After a median follow-up of 52 months, the 5-year cumulative incidence of locoregional recurrence (LRR) was 1.9%, 11.5% and 5.0% respectively (p < 0.01). At the multivariate analysis, extensive perivascular invasion, Luminal B HER2/Progesterone Receptor (PgR) negative status and Quadrantectomy followed by Intra-operative radiotherapy with electrons have significantly increased the risk of LRR. Our results suggest that HER2/neu positive breast cancer might have better outcomes when treated simultaneously with external radiotherapy and trastuzumab. Moreover, we underline the importance of PgR and further new stratification of risk among luminal subtypes.