Serum biomarkers in the diagnosis of periprosthetic joint infection: consolidated evidence and recent developments

Periprosthetic Joint Infection (PJI) represents one of the leading causes of revision prosthetic surgery, accounting for 25% of failed Total Knee Replacement (TKR) and 15% of failed Total Hip Replacement (THR). The search for a biomarker that, together with clinical and radiological findings, could improve the management of such a kind of patients is currently a big challenge for orthopaedic surgeons. This review aims (1) to assess the accuracy and the limitations of the traditional (Serum Erythrocytes Sedimentation Rate, C-reactive Protein, Procalcitonin, Interleukin 6, Tumor Necrosis Factor alpha), (2) and to analyse the emerging serum biomarkers (Presepsin, Toll-like Receptor 2, soluble urokinase-type Plasminogen Activator Receptor, Chemokine Ligand 2 and Osteopontin) in the diagnosis of PJI. A special attention will be given to the emerging serum biomarkers, that could play an important role as first-line investigations, in the screening of PJI in a close future.

La risonanza magnetica del feto

La RM fetale si candida come metodica di approfondimento nella diagnostica per immagini prenatale, dopo il classico approccio ecografico entrato ormai nel depistage di massa delle anomalie fetali. Il ricorso alla RM fetale ha una storia breve ma l'interesse dei vari autori a questa metodica è risultato crescente nell'ultimo decennio.

In questo lavoro viene presentata una breve revisione critica dei dati della letteratura con alcune annotazioni sulle diverse soluzioni tecniche proposte. Viene soprattutto discusso il problema legato ai movimenti fetali che tendono a degradare l'immagine RM dando particolare risalto alle manovre eco-guidate di curarizzazione fetale. Vengono quindi riportati i risultati su una casistica di 27 pazienti gravide in epoca gestazionale compresa tra il secondo ed il terzo trimestre, 22 delle quali sottoposte a curarizzazione fetale. In particolare sono presentati i diversi risultati RM in relazione al diverso dosaggio e al diverso agente curaro-simile impiegato e alcuni dettagli tecnici sull'esecuzione della RM fetale. In questa prima parte del nostro lavoro viene infine discussa l'anatomia normale del cervello fetale all'RM.

CAPACITIVE COUPLING ELECTRIC FIELDS IN THE TREATMENT OF VERTEBRAL COMPRESSION FRACTURES

Positive effects of Capacitive Coupling Electric Field (CCEF) stimulation are described for several orthopedic indications such as the healing of recent fractures, non-unions and spinal fusion, due to the capacity to involve the up-regulation of osteopromotive factors. In vitro studies on MC3T3-E1 bone cells showed that CCEF acts opening the plasma membrane voltage gated calcium channels, thus increasing the cytosolic calcium concentration and the phospholipase A2 (PLA2) activity. Cytosolic calcium activates the calmodulin pathway, thus resulting in an up-regulated expression of osteogenic genes, such as transforming growth factor-β superfamily genes (TGF-β1, -β2 -β3, bone morphogenetic protein-2 and -4), fibroblast growth factor (FGF)-2, osteocalcin (BGP) and alkaline phosphatase (ALP). PLA2 acts increasing the synthesis of Prostaglandin E2 (PGE2), which promotes osteogenesis by raising the cellular L-ascorbic acid uptake through the membrane carrier sodium vitamin C transporter-2 (SVCT-2). In vivo, Brighton et al. in a castration-induced osteoporosis animal model, demonstrated that CCEF was able to restore bone mass/unit volume in the rat vertebral body. To investigate the role of CCEF stimulation in vertebral bone marrow edema (VBME) its percentage was assessed in 24 patients with 25 acute vertebral compression fractures (VCFs) conservatively treated with CCEF (group A) or without CCEF (group B) using serial MR imaging follow-up at 0, 30, 60, 90 days. Pain and quality of life were assessed by visual analog scale (VAS) and Oswestry Low Back Disability Index (ODI) in the same periods. At 90 day follow-up the complete resolution of VBME was found only in group A (p=0.0001). A significant improvement of VAS (p=0.007) and ODI (p=0.002) was also observed in group A. This preliminary observational study shows that patients treated with CCEF stimulation present an improvement of clinical symptoms with faster fracture healing and a complete VBME resolution.

Magnetic resonance imaging screening of cerebral thromboembolic events in children with acute lymphoblastic leukemia: a pilot study

BACKGROUND

Thromboembolism is a complication of acute lymphoblastic leukemia therapy in children. The majority of thromboembolic events are cerebral thromboses and deep venous thromboses; many asymptomatic deep venous thromboses are detected in children with acute lymphoblastic leukemia by instrumental screening. The aim of this study was to assess the incidence of asymptomatic cerebral thromboembolic events in children with acute lymphoblastic leukemia (ALL) screened by magnetic resonance imaging and magnetic resonance venography.

METHODS

46 children with acute lymphoblastic leukemia, during the induction phase of the AIEOP ALL 2000 protocol, were stratified into 2 groups. In group "A" cerebral thromboembolic events were suspected following the appearance of suggestive signs and symptoms and confirmed by cerebral magnetic resonance imaging and magnetic resonance venography; in group "B" children underwent a screening by cerebral magnetic resonance imaging and magnetic resonance venography, at set times, in absence of symptoms.

RESULTS

We observed one cerebral thromboembolic event in both groups; we found no differences between early detecting asymptomatic cerebral thromboembolic events among monitored and not monitored patients.

CONCLUSIONS

Our study does not seem to suggest a screening for asymptomatic cerebral thromboembolic events in children with ALL during the induction phase.

A case of aneurysm on a persistent hypoglossal artery treated by endovascular coiling

SUMMARY

We describe a 22-year-old woman admitted to hospital in emergency with nuchal headache and vomiting. CT scan disclosed subarachnoid hemorrhage. Digital subtraction angiography with three-dimensional rotational acquisitions showed a ruptured aneurysm of a right persistent primitive hypoglossal artery as the cause of symptoms and hemorrhage. The patient was successfully treated with endovascular coiling of the aneurysm. This is the second literature report describing endovascular treatment in this unusual condition.

Hereditary hemorrhagic telangiectasia: clinical features in ENG and ALK1 mutation carriers

BACKGROUND

Hereditary hemorrhagic telangiectasia (HHT) is a genetic disorder characterized by epistaxis, mucocutaneous telangiectases and visceral arteriovenous malformations (AVMs), particularly in the brain (CAVMs), lungs (PAVMs), liver (HAVMs) and gastrointestinal tract (GI). The identification of a mutated ENG (HHT1) or ALK-1 (HHT2) gene now enables a genotype-phenotype correlation.

OBJECTIVE

To determine the incidence of visceral localizations and evaluate phenotypic differences between ENG and ALK1 mutation carriers.

METHODS

A total of 135 consecutive adult patients were subjected to mutational screening in ENG and ALK1 genes and instrumental tests to detect AVMs, such as chest-abdomen multislice computed tomography (MDCT), brain magnetic resonance imaging and magnetic resonance angiography (MRI/MRA), upper endoscopy, were offered to all patients, independent of presence of clinical symptoms. The 122 patients with identified mutations were enrolled in the study and genotype-phenotype correlations were established.

RESULTS

PAVMs and CAVMs were significantly more frequent in HHT1 (75% vs. 44%, P < 0.0005; 20% vs. 0%, P < 0.002, respectively) and HAVMs in HHT2 (60% vs. 84%, P < 0.01). No age difference was found for PAVMs whereas HAVMs were significantly higher in older patients in both HHT1 and HHT2. Neurological manifestations secondary to CAVMs/PAVMs were found only in HHT1 patients, whereas severe liver involvement was detected only in HHT2. Respiratory symptoms were mainly detected in HHT1.

CONCLUSIONS

Our study evidences a higher visceral involvement in HHT1 and HHT2 compared with previous reports. HHT1 is more frequently associated with congenital AVM malformations, such as CAVMs and PAVMs whereas HHT2 predominantly involves the liver. The ENG gene should be first targeted for mutational screening in the presence of large PAVM in patients < 45 years.

Whole-brain and regional brain atrophy in amyotrophic lateral sclerosis

BACKGROUND AND PURPOSE

Recent evidence from neuropsychologic and neuroimaging studies suggests that central nervous system involvement in amyotrophic lateral sclerosis (ALS) extends beyond motor neurons. Our purpose was to obtain measures of global and regional atrophy in nondemented patients with ALS to assess subtle structural brain changes.

METHODS

MR images, acquired from 16 patients and 9 healthy subjects (HS), were processed by using the Structural Imaging Evaluation of Normalized Atrophy (SIENA) software to estimate whole-brain atrophy measures and the voxel-based morphometry (VBM) method to highlight the selective volumetric decrease of single cerebral areas. In addition, each subject underwent a neuropsychologic examination.

RESULTS

In patients with ALS, brain parenchymal fraction was slightly lower compared with HS (P = .012), and seemed to be related to the presence of cognitive impairment. Patients showed a gray matter volume decrease in several frontal and temporal areas bilaterally (P < .001 uncorrected) compared with HS, with a slight prevalence in the right hemisphere. No volume reduction in primary motor cortices of patients was detected. Performances on Symbol Digit Modalities Test were significantly worse in patients compared with HS (P = .025).

CONCLUSIONS

The presence of mild whole-brain volume loss and regional frontotemporal atrophy in patients with ALS could explain the presence of cognitive impairment and confirms the idea of ALS as a degenerative brain disease not confined to motor system.

Antenatal diagnosis of isolated lissencephaly by ultrasound and magnetic resonance imaging

Lissencephaly (agyria) is a cortical dysplasia associated with a disturbance in the migration of neocortical neurons. Because of abnormal sonographic findings in the brain of a 24-week fetus, we carried out serial magnetic resonance imaging (MRI) examinations which raised the suspicion of isolated lissencephaly. In the second trimester, an area of damage depicted as low-intensity signals was identified by MRI inside the cortical parenchyma. In the same cortical area, agyria was detected later in pregnancy, and postnatally calcification was observed by computerized tomography (CT) scan. We believe that ultrasound and targeted MRI examination can improve our understanding of some disorders of neuronal migration and that earlier diagnosis is feasible if both methods are employed and interpreted by sound criteria.

Imaging studies in partial epilepsy in children and adolescents

We reviewed the results of imaging studies on 111 children and adolescents with partial epilepsy to determine which imaging procedure had the greatest sensitivity and specificity for partial epilepsy in this age range. All cases were classified as idiopathic, lesional, and cryptogenic epilepsy based on the 1989 International League Against Epilepsy Classification. All patients had magnetic resonance imaging (MRI) and 98 also had computed tomography (CT). Thirty patients with negative CT had MRI lesions that were most likely the cause of the epilepsy, and the initial diagnosis of cryptogenic partial epilepsy was changed to lesional partial epilepsy. We concluded that CT use is unwarrantedly common. MRI should be considered the procedure of first choice. CT has a complementary role, and functional neuroimaging should be encouraged.

[Staging of spinal metastasis using special techniques of magnetic resonance imaging]

The diagnosis of spine metastasis is a problem of great interest which leaves many questions unanswered. In this field MR imaging plays a fundamental role, as the only technique able to directly demonstrate the changes in bone marrow tissue, bound to tumoral activity. The introduction of gradient-echo (GE) sequences has helped reduce examination time. Moreover, with the accurate choice of pulse-sequence parameters (TR, TE, flip angle) additional information is acquired which is not yielded by conventional spin-echo (SE) sequences. Our study was aimed at evaluating MR sensitivity in the different stages of bone metastatic evolution. The comparative adequacy was evaluated of combined bone scintigraphy and conventional radiology versus MR imaging in 62 patients with vertebral metastases. Time interval between bone scan and/or radiological study and MR exam ranged from 10 days to 8 months. SE and GE T1-weighted images, and SE and GE T2-weighted images on the sagittal plane were employed, and axial images; coronal images were rarely acquired. Metastases were demonstrated by MR imaging at 122 vertebral levels, versus 88 true positives of combined scintigraphy and conventional radiology. Scintigraphic false-positives were observed at 15 vertebral levels, versus 9 with radiography. GE sequences were superior to SE ones in detecting vertebral morphologic lesions and bone marrow involvement thanks to their improved resolution and sensitivity. Moreover, GE sequences demonstrated tumoral bone marrow spread and persistent tumoral activity in the follow-up of spine metastases. Our results point to GE sequences as those of choice because of their higher resolution and sensitivity, which also allow response to treatment to be evaluated.

Smooth pursuit eye movements among storage battery workers

Eleven male workers in a battery storage plant with lead and erythrocyte protoporphyrin blood actual levels greater than 50 and 100 micrograms %, respectively, and 18 male controls without lead exposure were tested by a clinical pendular eye tracking test (PETT). Each worker underwent a series of lead absorption measurements including blood lead, urinary lead, erythrocyte protoporphyrin, delta-aminolevulinic acid dehydratase activity, and urinary delta-aminolevulinic acid. The SPEMs were evaluated by an eye tracking technique. The subjects followed a horizontally moving target which, in the form of a luminous spot on a dark background, was projected onto a screen placed 1 m from the subject. The maximum predicted eye movement velocity during tracking was about 30 degrees/s. Skin electrodes were applied on the outer canthi of both eyes and SPEM were plotted on a polygraph, recording both the actual eye movements and the corresponding first derivative. Our findings suggest that lead workers display a disorder of motor coordination of SPEMs system, and the PETT is useful, when associated with biochemical data, to evaluate the degree of subclinical damage of nervous system during lead poisoning.