Päivi Jalava-Karvinen

Simultaneous quantitative analysis of FcγRI (CD64) and CR1 (CD35) on neutrophils in distinguishing between bacterial infections, viral infections, and inflammatory diseases

A flow cytometric quantitative analysis of receptors on neutrophils can be exploited in distinguishing between inflammatory and infectious diseases. In this prospective comparative study, simultaneous quantitative analysis of CD64 and CD35 on peripheral blood neutrophils was performed in febrile patients in order to differentiate between bacterial infections (n=89), viral infections (n=46), and inflammatory diseases (n=21). The patient data was compared to 60 healthy controls. We could divide patients into three groups depending on how they express CD35 and CD64 on neutrophils: (1) patients with a high probability of viral infection (low CD35/low CD64 and low CD35/high CD64), (2) patients with a high probability of inflammatory disease (high CD35/low CD64), and (3) patients with a high probability of bacterial infection (high CD35/high CD64). In summary, simultaneous quantitative analysis of CD64 and CD35 on neutrophils could potentially assist physicians to distinguish between inflammatory and infectious diseases.

Use of complement regulators, CD35, CD46, CD55, and CD59, on leukocytes as markers for diagnosis of viral and bacterial infections.

Several complement regulatory proteins exist on self-cells to prevent damage by the serum complement system. In the present study, we aimed to perform quantitative analysis of membrane-bound complement regulators, CR1 (CD35), MCP (CD46), DAF (CD55), and MIRL (CD59), on peripheral blood neutrophils, monocytes, and lymphocytes from healthy controls (n=36) and febrile patients diagnosed with either bacterial (n=21) or viral (n=26) infections. Our results show that: (a) increased CD35 and CD55 levels on neutrophils and monocytes present potent markers of bacterial infection, (b) increased expression of CD46 on monocytes is an indicator of viral infection, and (c) increased CD59 expression on neutrophils and monocytes is a general infection marker. Additionally, CD19-positive B-lymphocytes represent practically the only lymphocyte population capable of expressing CD35. We further developed two novel clinical flow cytometric markers (indices), specifically, clinical mononucleosis (CM)-INDEX (incorporating CD35, CD55, and CD59 expression on lymphocytes) and clinical bacterial infection (CBI)-INDEX (incorporating CD35 and CD55 expression on neutrophils and lymphocytes), for the effective detection of viral mononucleosis and bacterial infection, respectively. In summary, bacterial and viral infections induce different expression patterns of membrane-bound complement regulators in human leukocytes, which may be effectively exploited in clinical differential diagnosis.

CRP/CD11b ratio: a novel parameter for detecting gram-positive sepsis.

To commence proper antibiotic treatment in sepsis, timely knowledge of whether the cause of systemic infection is gram-negative (gram(-)) or gram-positive (gram(+)) bacteria in origin would be beneficial for clinicians. In this clinical prospective study, our objective was to develop a method for distinguishing between gram(+) and gram(-) bacterial infection. In gram(-) bacterial infection (n = 21), the average amount of CD11b on neutrophils was significantly higher than in gram(+) bacterial infection (n = 22). On the contrary, serum C-reactive protein (CRP) level was significantly higher in gram(+) than in gram(-) bacterial infection. By dividing the serum CRP value by the amount of CD11b on neutrophils, we derived a novel marker of gram(+) sepsis, CRP/CD11b ratio, which displayed 76% sensitivity and 80% specificity for the detection of gram(+) sepsis (n = 17) among febrile patients with microbiologically confirmed or clinically diagnosed bacterial infection. The detection of gram(+) sepsis is possible after the combination of neutrophil CD11b data and serum CRP level. In conclusion, our findings indicate that the proposed CRP/CD11b ratio test could potentially assist physicians in determining an appropriate antibiotic treatment in patients with severe bacterial infection.

Imported tungiasis in a Finnish journalist: the first case reported from the Nordic countries

Tungiasis is a parasitic infection widely spread in tropical Africa and in South and Central America. Only a few cases involving travellers have been reported from Europe, and none from the Nordic countries. We report a case of tungiasis in a Finnish journalist returning from Uganda. In this era of increasing intercontinental travel it is important that all physicians are aware of tungiasis.

Metastasis in the temporal bone mimicking temporal arteritis.

This report describes a 72-year-old female patient with a previous history of cured breast cancer who presented with acute monocular visual disturbances, intense unilateral headache, painful temporal artery palpation, high erythrocyte sedimentation rate, and pain and weakness of the femoral muscles. These symptoms and signs were suggestive of temporal arteritis, but the finding of the temporal artery biopsy was negative, and the patient did not respond to corticosteroid treatment. Later, whole body bone scintigraphy revealed dissemination of malignancy throughout her skeleton including the skull. To our knowledge, this is the first report to show that a metastasis in the temporal bone can closely mimic temporal arteritis.

Scedosporium apiospermum as a rare cause of central skull base osteomyelitis

We report a case of Scedosporium apiospermum mold causing ear infection, central skull base osteomyelitis and finally, occlusion of carotid artery in a 48-year-old diabetic man. The exact diagnosis was established and the severity of the disease understood several months after the onset of symptoms. Despite of appropriate antifungal therapy, and repeated surgical and otological procedures, the infection progressed to fatal cerebral infarction.

A single-tube two-color flow cytometric method for distinguishing between febrile bacterial and viral infections

The aim of this study was to develop a rapid single-tube two-color flow cytometric method to distinguish between febrile bacterial and viral infections. In this prospective comparative study, the quantitative flow cytometric analysis of CD35 and CD64 on isolated human leukocytes was obtained from 286 hospitalized febrile patients, of which 197 patients were found to have either a bacterial (n = 136) or viral (n = 61) infection. The data from infected patients was compared to 49 healthy controls and 23 patients in an inflammatory state. We developed a flow cytometric marker for bacterial infections, defined as the two-color bacterial infection index (TC-BI-index), by incorporating the quantitative analysis of CD35 and CD64 on isolated neutrophils, monocytes, and B-lymphocytes, which displayed 90% sensitivity and specificity in distinguishing between microbiologically confirmed bacterial (n = 77) and viral infections (n = 61) within 45 min. We propose that TC-BI-index test will be useful in assisting physicians to ascertain whether antibiotic treatment is required, thus limiting unnecessary antimicrobial usage.

Capnocytophaga canimorsus: a rare case of conservatively treated prosthetic valve endocarditis

We describe a rare case of prosthetic valve endocarditis caused by the canine bacterium Capnocytophaga canimorsus in a male aged 73 years. The diagnosis of infective endocarditis was unequivocal, as it blood cultures were positive for C. canimorsus and vegetations were detected on transesophageal echocardiography; the modified Duke criteria were fulfilled. PET‐CT showed intense 18F‐FDG uptake of the prosthetic valve area. The patient was treated with antibiotics alone (no surgery), and is now on life‐long suppressive antibiotic therapy. To our knowledge, this is the third reported case of prosthetic valve endocarditis caused by C. canimorsus and the first one to have been treated conservatively.