Prevalence of potential underlying aetiology of macrocytic anaemia in Dutch general practice

A Cross-Sectional Study for the Spectrum of Clinical Diagnosis in Patients Presenting With Macrocytosis

Objective The objectives of this study were to determine the frequency of the clinical spectrum of diseases in patients with macrocytosis and to summarize the diagnostic evaluation of patients found to have macrocytosis on laboratory testing. Background This was a cross-sectional study that took place at the Department of Medicine in Combined Military Hospital, Rawalpindi, Pakistan, from January to June 2023. Methodology One hundred and five patients with macrocytosis with mean corpuscular volume (MCV) values > 100 fL (80 to 100 fL) were inducted as per inclusion and exclusion criteria. Informed consent was obtained from all patients. Complete blood counts (CBC), peripheral blood film, serum vitamin B12 levels, serum folate levels, renal function tests (RFTs), liver function tests (LFTs), and thyroid function tests (TFTs) were performed during the assessment. Results The commonest cause of macrocytosis was vitamin B12 deficiency followed by folate deficiency, combined vitamin B12 and folate deficiency, and other causes were also found in a few cases. Conclusion Serum vitamin B12 and folate deficiency are the most common preventable causes of macrocytosis.

Important reminder: nitrous oxide (N2O) as a cause of functional vitamin B12 deficiency

A 32-year-old woman who misused multiple substances, including nitrous oxide (N₂O), sought medical advice after she subacutely developed bilateral lower extremity weakness without a sensory level but with ataxia-her significant other developed similar symptoms with vitamin B₁₂ deficiency due to N₂O intake. Laboratory results revealed macrocytic anaemia despite normal B₁₂ and folate levels, with serum markers pointing towards functional cobalamin deficiency. Spinal MRIs and cerebrospinal fluid analysis were unremarkable. Our patient was treated with vitamin B₁₂ supplementation with an encouraging response.

Experimental and Theoretical Approaches to Describing Interactions in Natural Cell Membranes Occurring as a Result of Fatal Alcohol Poisoning

We propose herein a theoretical model describing the effect of fatal ethanol poisoning on the equilibria between cell membranes and the surrounding ions. Using this model, we determined the parameters characterizing the interaction between the electrolyte solution’s ions and the functional groups on the blood cells’ surface. Via the application of mathematical equations, we calculated the total surface concentrations of the acidic and basic groups, c_A and c_B, and their association constants with solution ions, K_AH and K_BOH. Using the determined parameters and mathematical equations’ values, we calculated the theoretical surface charge density values. We verified the proposed model by comparing these values with experimental data, which were selected based on measurements of the electrophoretic mobility of erythrocyte and thrombocyte membranes. Compatibility of the experimental and theoretical surface charge density values was observed in the range of pH 2–8, while deviations were observed at higher pH values.

Autoimmune Hemolytic Anemia After Cyanocobalamin Replacement in a Patient With a Previous Diagnosis of Pernicious Anemia: A Case Report

Pernicious anemia (PA) is associated with other autoimmune diseases, such as hypothyroidism, type 1 diabetes mellitus (DM1), Addison's disease, and vitiligo. The association between PA and autoimmune hemolytic anemia (AIHA) is rare, with less than 30 cases reported in the literature. In this paper, we report a case of a patient with a confirmed diagnosis of PA, who, six months after starting treatment with cyanocobalamin, presented with severe hemolysis with a positive direct antiglobulin test (DAT) for warm antibodies; the patient responded well to glucocorticoid treatment. AIHA in PA patients can be triggered by cyanocobalamin replacement due to the expression of membrane antigens by mature red blood cells entering into the peripheral circulation. This association should be considered because these patients, in addition to cyanocobalamin replacement, will require immunosuppressive treatment, usually with glucocorticoids.

Vitamin B12 deficiency and clinical laboratory: Lessons revisited and clarified in seven questions

The objective of this review article is to address the most frequently asked questions that pathologists and primary care physicians might face when dealing with a patient with suspicion of vitamin B12 deficiency. More specifically, the article mainly discusses the importance and prevalence of the deficit, how to recognize it, and the important role of a prompt diagnosis confirmation based on laboratory biomarkers for efficient replacement therapy.

Diagnostics in anaemia of chronic disease in general practice: a real-world retrospective cohort study

Background

Limited research has been performed that focused on the diagnosis of the underlying cause of anaemia of chronic disease (ACD) in general practice or on prevalence data of the underlying causes of ACD in general practice, although this is one of the most common types of anaemia.

Aim

To clarify the diagnostic strategies of GPs in patients newly diagnosed with ACD and to determine the most common underlying causes.

Design & setting

Retrospective cohort study.

Method

Patients newly diagnosed with ACD were selected based on laboratory criteria. ACD was defined as confirmed anaemia and ferritin levels above 100 μg/l combined with decreased iron and/or reduced transferrin. Additional medical information on patients was obtained from the electronic medical files of the GP and/or the referral hospital.

Results

Of the 267 analysed patients with ACD, additional investigations were performed in 205 patients (77%); in 31 patients (12%) the cause was apparent at the time of diagnosis, and for 31 patients (12%) no additional investigations were requested. In 210 (79%) of the 267 patients, an underlying cause was established, with infection (n = 68, 32%), autoimmune disease (n = 51, 24%) and malignancy (n = 48, 23%) as the most frequently observed etiologies. In 35 (13%) of the ACD patients, oral iron supplementation was prescribed by the GP. This was mainly done in patients with severe anaemia or less enhanced ferritin levels.

Conclusion

For most patients with newly diagnosed ACD, the GP undertakes additional investigations to establish underlying causes. However, the cause of ACD remains unknown in a small proportion of patients. The use of oral iron supplementation in these patients requires caution.

The effectiveness of a routine versus an extensive laboratory analysis in the diagnosis of anaemia in general practice

Background

We investigated the percentage of patients diagnosed with the correct underlying cause of anaemia by general practitioners when using an extensive versus a routine laboratory work-up.

Methods

An online survey was distributed among 836 general practitioners. The survey consisted of six cases, selected from an existing cohort of anaemia patients ( n = 3325). In three cases, general practitioners were asked to select the laboratory tests for further diagnostic examination from a list of 14 parameters (i.e. routine work-up). In the other three cases, general practitioners were presented with all 14 laboratory test results available (i.e. extensive work-up). General practitioners were asked to determine the underlying cause of anaemia in all six cases based on the test results, and these answers were compared with the answers of an expert panel.

Results

A total of 139 general practitioners (partly) responded to the survey (17%). The general practitioners were able to determine the underlying cause of anaemia in 53% of cases based on the routine work-up, whereas 62% of cases could be diagnosed using an extensive work-up ( P = 0.007). In addition, the probability of a correct diagnosis decreased with the patient’s age and was also affected by the underlying cause itself, with anaemia of chronic disease being hardest to diagnose ( P = 0.003).

Conclusion

The use of an extensive laboratory work-up in patients with newly diagnosed anaemia is expected to increase the percentage of correct underlying causes established by general practitioners. Since the underlying cause can still not be established in 31.3% of anaemia patients, further research is necessary.