Clozapine is an atypical antipsychotic crucial for treatment-resistant schizophrenia, characterised by its multi-receptor targeting, including serotonin (5-HT2A, 5-HT2C) and dopamine (D1, D2, D3, D4) receptors, among others. This broad mechanism is effective against positive symptoms of schizophrenia with a lower incidence of extrapyramidal side effects. However, clozapine poses significant haematological risks, notably agranulocytosis, necessitating stringent blood monitoring protocols.

This study examined haematological parameters in 157 patients on clozapine therapy, analysing the prevalence and clinical correlations of haematological abnormalities such as leucocytosis, thrombocytosis, and alterations in red blood cell distribution width (RDW) and mean platelet volume (MPV).

The findings revealed leucocytosis in 36.9% of patients, thrombocytosis in 8.9%, and elevated RDW in 23.6%. Notably, higher clozapine doses were associated with leucocytosis, though no significant correlations were found between clozapine dose, duration of use, and changes in RDW, mean corpuscular haemoglobin concentration, or MPV.

The study’s results underscore the necessity of regular haematological monitoring to mitigate the risks of clozapine therapy while leveraging its therapeutic benefits. Additionally, the study suggests personalised dosing strategies to balance efficacy and safety, particularly in managing clozapine-induced haematological changes.

The most serious manifestation of rheumatic fever is carditis, as it can lead to chronic rheumatic heart disease. Neutrophil-to-lymphocyte ratio, platelet-to lymphocyte ratio and mean platelet volume have been accepted as novel indicators of the continuing inflammation that is correlated with the severity of valvular involvement in patients with rheumatic carditis.

As a diagnostic study to investigate the correlation of neutrophil-to-lymphocyte ratio, platelet-to-lymphocyte ratio and mean platelet volume with the severity of carditis in children with rheumatic fever.

This was a cross-sectional study at Sanglah Hospital, Bali. Data were collected retrospectively from medical records. Severity of carditis was characterised by a clinical, audible murmur during physical examination and demonstration of valvular involvement by echocardiography. Neutrophil-to-lymphocyte ratio, platelet-to-lymphocyte ratio and mean platelet volume were calculated from complete blood count. The correlation between parameters was assessed using Spearman’s correlation tests.

From January 2018 to December 2020, we found 45 cases admitted to Sanglah Hospital. Carditis was present in 40 (88.9%) subjects. Neutrophil-to-lymphocyte ratio had a strong positive correlation with severity of carditis (r = 0.66, p = 0.001), while platelet-to-lymphocyte ratio had a weak positive correlation with the severity of carditis (r = 0.23, p = 0.13) and mean platelet volume had a very weak negative correlation with the severity of carditis (r = −0.01, p = 0.95). Using a cut-off of 3.4, neutrophil-to-lymphocyte ratio predicted severe carditis with a sensitivity of 81.8% and specificity of 91.3%.

There was a positive correlation between neutrophil-to-lymphocyte ratio and severity of carditis in children with rheumatic fever. Neutrophil-to-lymphocyte ratio might be used as a diagnostic tool to predict the diagnosis of carditis severity.

To assess the diagnostic role of mean platelet volume in tonsillitis with and without peritonsillar abscess.

Mean platelet volume and other laboratory data were retrospectively investigated.

Mean platelet volume was significantly lower in the tonsillitis group (7.8 per cent ± 0.7 per cent) than in the control group (8.7 per cent ± 0.6 per cent; p < 0.0001), and it was significantly lower in the abscess group (7.5 per cent ± 0.6 per cent) than in the no abscess group (8.0 per cent ± 0.7 per cent; p = 0.0277). White blood cell counts and C-reactive protein levels were not significantly different between patients with an abscess and those without. The mean platelet volume cut-off values for the diagnosis of tonsillitis and peritonsillar abscess were 7.95 fl and 7.75 fl, respectively.

Our results suggest that a decreased mean platelet volume is associated with the development and severity of tonsillitis. This finding provides useful diagnostic information for physicians treating patients with tonsillitis.

This study aimed to evaluate patients with tinnitus in terms of mean platelet volume and platelet distribution width, and to explore neutrophil-to-lymphocyte ratio and platelet-to-lymphocyte ratio, recently reported in the literature as being possible inflammation markers.

This study comprised 64 tinnitus patients and 64 age-matched healthy controls. Statistical significance level was accepted as p < 0.05.

Mean platelet volume (t = 3.245, p = 0.002) and platelet distribution width (Z = 3.945, p < 0.001) were significantly higher in the patient group than the control group.

The results suggest that a prothrombotic condition might play a role in the pathophysiology of tinnitus.

The aim of the present study was to investigate the relationships between red blood cell distribution width, platelet distribution width, and mean platelet volume and the presence and severity of valvular involvement in patients with rheumatic heart disease.

Between April, 2012 and December, 2015, 151 patients who were admitted to the Pediatric Cardiology Unit with diagnosis of rheumatic heart disease and 148 healthy children were included to our study. Transthoracic echocardiography for all children was performed, and the values of red blood cell distribution width, platelet distribution width, and mean platelet volume, besides other blood count parameters, erythrocyte sedimentation rate, and C-reactive protein levels were recorded.

Red blood cell distribution width, platelet distribution width, mean platelet volume, and C-reactive protein levels were significantly higher in patients with rheumatic heart disease when compared with healthy controls (p<0.01). Red blood cell distribution width was positively correlated with both C-reactive protein (r=0.271, p=0.035) and erythrocyte sedimentation rate (r=0.308, p=0.006). When single valve involvement was compared with both aortic valve and mitral valve involvement in the study group, red blood cell distribution width and platelet distribution width were higher in patients with double valve involvement; however, this was not statistically significant (p>0.05).

This is the first study in children with rheumatic heart disease that demonstrated significantly increased red blood cell distribution width, platelet distribution width, and mean platelet volume levels, as well as evaluated all three parameters together. Furthermore, red blood cell distribution width values in the chronical period of acute rheumatic fever, due to the positive correlation with the other chronic inflammatory markers, may help make the diagnosis in children.

To investigate new inflammatory markers in patients with laryngopharyngeal reflux and determine whether these inflammatory parameters change in response to laryngopharyngeal reflux treatment.

Complete blood count was evaluated to obtain platelet count and mean platelet volume and calculate neutrophil-to-lymphocyte ratio and platelet-to-lymphocyte ratio. Laryngopharyngeal reflux patients underwent three-month lansoprazole treatment.

The study included 45 laryngopharyngeal reflux patients (9 men (20 per cent); mean age, 37.4 ± 11.6 years) and 35 healthy age- and sex-matched controls (7 men (20 per cent); mean age, 38.6 ± 8.9 years). The study group had significantly higher platelet-to-lymphocyte ratios and lower mean platelet volumes than the control group (p = 0.004 and p = 0.047, respectively). There was a significant correlation between platelet-to-lymphocyte ratios and initial inflammatory symptoms (reflux symptom index, p = 0.025; reflux finding score, p = 0.013). There was also a significant correlation between mean platelet volume increase and symptom resolution in the first and third months of treatment (p = 0.04 and p = 0.03, respectively).

Platelet-to-lymphocyte ratio, a new inflammatory marker of chronic inflammation, was significantly higher in laryngopharyngeal reflux patients. Moreover, these patients had significantly lower mean platelet volume values, which increased with post-treatment symptom improvement.

This study aimed to determine whether there was any relationship between tinnitus and mean platelet volume.

This retrospective study was conducted between January 2013 and January 2014 in Ankara Atatürk Hospital and Ondokuz Mayıs University Hospital, Turkey, on a study group of 86 patients with tinnitus and a control group of 84 healthy subjects. Mean platelet volume was recorded and comparisons were made between the two groups.

Mean (± standard deviation) platelet volume was 7.67 ± 0.83 μm3 in the study group and 7.28 ± 0.56 μm3 in the control group. There was a statistically significant difference in mean platelet volume between the tinnitus patients and the healthy subjects (p < 0.05).

The clinical findings indicated that tinnitus patients had a higher mean platelet volume than the healthy control subjects; however, the pathophysiological mechanism remains unclear.

Previous studies investigating the known risk factors of atherosclerosis in phenylketonuria patients have shown conflicting results. The primary aim of our study was to investigate the serum atherogenic markers in adolescent classical phenylketonuria patients and compare these parameters with healthy peers. The secondary aim was to compare these atherogenic markers in well-controlled and poorly controlled patients.

A total of 59 patients (median age: 12.6 years, range: 11–17 years) and 44 healthy controls (median age: 12.0 years, range: 11–15 years) were enrolled in our study. Phenylketonuria patients were divided into two groups: well-controlled (serum phenylalanine levels below 360 µmol/L; 24 patients) and poorly controlled patients (serum phenylalanine levels higher than 360 µmol/L).

The mean high-density lipoprotein cholesterol levels of well-controlled patients (1.0±0.2 mmol/L) were significantly lower compared with poorly controlled patients and controls (1.1±0.2 mmol/L, p=0.011 and 1.4±0.2 mmol/L, p<0.001, respectively). Poorly controlled patients had lower high-density lipoprotein cholesterol levels than healthy controls (p=0.003). Homocysteine levels of both well-controlled (9.8±6.4 µmol/L) and poorly controlled (9.2±5.6 µmol/L) patients were higher compared with controls (5.8±1.8 µmol/L, p<0.01). The mean platelet volume of well-controlled patients (9.5±1.1 fL) was higher than that of poorly controlled patients and controls (8.9±0.8 fL, p=0.024 and 7.7±0.6 fL, p<0.001, respectively).

Lower high-density lipoprotein cholesterol and higher homocysteine and mean platelet volume levels were detected in phenylketonuria patients. In particular, these changes were more prominent in well-controlled patients. We conclude that phenylketonuria patients might be at risk for atherosclerosis, and therefore screening for atherosclerotic risk factors should be included in the phenylketonuria therapy and follow-up in addition to other parameters.