Precision diagnosis and therapy of a case of brain abscesses associated with asymptomatic pulmonary arteriovenous fistulas.

BACKGROUND: Brain abscesses, a severe infectious disease of the CNS, are usually caused by a variety of different pathogens, which include Streptococcus intermedius (S. intermedius). Pulmonary arteriovenous fistulas (PAVFs), characterized by abnormal direct communication between pulmonary artery and vein, are a rare underlying cause of brain abscesses. CASE PRESENTATION: The patient was a previous healthy 55-year-old man who presented with 5 days of headache and fever. Cerebral magnetic resonance imaging (MRI) suggested a brain abscess. Thoracic CT scan and angiography demonstrated PAVFs. Aiding by metagenomic next-generation sequencing (mNGS) of the cerebrospinal fluid (CSF) sample which identified S. intermedius as the causative pathogen, the patient was switched to the single therapy of large dose of penicillin G and was cured precisely and economically. CONCLUSIONS: It is an alternative way to perform mNGS to identify causative pathogens in patients with brain abscesses especially when the results of traditional bacterial culture were negative. Further thoracic CT or pulmonary angiography should also be undertaken to rule out PAVFs as the potential cause of brain abscess if the patient without any known premorbid history.

Recurring Thalamic Symptoms Due to Intracranial Dural Arteriovenous Fistula: Report of Unusual Case and Treatment Outcome.

BACKGROUND: Initial clinical presentation of dural arteriovenous fistula (DAVF) with predominantly thalamic symptoms is rare and has not been reported until now. CASE DESCRIPTION: A young child presenting with complaints of tinnitus and mild right hemiparesis was evaluated with an initial magnetic resonance imaging, which revealed a Borden type 2 DAVF in the right transverse sinus with retrograde venous drainage and cortical venous reflux. Flow-related small aneurysms were also noted in the left basal vein of Rosenthal (BVR). Two days later, his motor power deteriorated and he developed right hemisensory loss and severe thalamic pain. Aphasia was atypical and mimicked the transcortical type. Repeat imaging revealed expanding thrombosed aneurysm of BVR with mass effect and edema on thalamocapsular region. Initial antiedema measures reversed the neurologic deficits; however, they recurred, necessitating an urgent endovascular intervention. Angiogram revealed an extensive high-flow DAVF in the right transverse-sigmoid sinus and torcula with preferential retrograde venous drainage into deep veins and left BVR. He underwent staged embolization of DAVF, resulting in significant obliteration of shunt. Neurologic deficits improved in the postoperative period, and the patient remained clinically asymptomatic at 6 months of follow-up. CONCLUSIONS: DAVF presenting with recurrent predominantly thalamic symptoms is rare. Atypical transcortical aphasia rather than fluent aphasia is an unusual clinical manifestation of thalamic pathology and could result from the involvement of specific thalamic nuclei. Preferential high flow into BVR in the presence of venous anomalies could potentially induce architectural weakness of the venous wall and precipitate aneurysm formation. Embolization of the DAVF can potentially reverse this unusual neurologic condition.

The pathogenesis of hemodialysis vascular access failure and systemic therapies for its prevention: Optimism unfulfilled.

In patients receiving hemodialysis, the provision of safe and effective vascular access using an arteriovenous fistula or graft is regarded as a critical priority by patients and health professionals. Vascular access failure is associated with morbidity and mortality, such that strategies to prevent these outcomes are essential. Inadequate vascular remodeling and neointimal hyperplasia resulting in stenosis and frequently thrombosis are critical to the pathogenesis of access failure. Systemic medical therapies with pleiotropic effects including antiplatelet agents, omega-3 polyunsaturated fatty acids (fish oils), statins, and inhibitors of the renin-angiotensin-aldosterone system (RAAS) may reduce vascular access failure by promoting vascular access maturation and reducing stenosis and thrombosis through antiproliferative, antiaggregatory, anti-inflammatory and vasodilatory effects. Despite such promise, the results of retrospective analyses and randomized controlled trials of these agents on arteriovenous fistula and graft outcomes have been mixed. This review describes the current understanding of the pathogenesis of arteriovenous fistula and graft failure, the biological effects of antiplatelet agents, fish oil supplementation, RAAS blockers and statins that may be beneficial in improving vascular access survival, results from clinical trials that have investigated the effect of these agents on arteriovenous fistula and graft outcomes, and it explores future therapeutic approaches combining these agents with novel treatment strategies.

Risk factors for pulmonary hypertension in patients receiving maintenance peritoneal dialysis

We investigated the risk factors for pulmonary hypertension (PH) in patients receiving maintenance peritoneal dialysis (MPD). A group of 180 end-stage renal disease patients (124 men and 56 women; mean age: 56.43±8.36) were enrolled in our study, which was conducted between January 2009 and June 2014. All of the patients received MPD treatment in the Dialysis Center of the Second Affiliated Hospital of Soochow University. Clinical data, laboratory indices, and echocardiographic data from these patients were collected, and follow-ups were scheduled bi-monthly. The incidence and relevant risk factors of PH were analyzed. The differences in measurement data were compared by t-test and enumeration data were compared with the χ2 test. Among the 180 patients receiving MPD, 60 were diagnosed with PH. The remaining 120 were regarded as the non-PH group. Significant differences were observed in the clinical data, laboratory indices, and echocardiographic data between the PH and non-PH patients (all P<0.05). Furthermore, hypertensive nephropathy patients on MPD showed a significantly higher incidence of PH compared with non-hypertensive nephropathy patients (P<0.05). Logistic regression analysis showed that the proportion of internal arteriovenous fistula, C-reactive protein levels, and ejection fraction were the highest risk factors for PH in patients receiving MPD. Our study shows that there is a high incidence of PH in patients receiving MPD and hypertensive nephropathy patients have an increased susceptibility to PH.

Risk factors for pulmonary hypertension in patients receiving maintenance peritoneal dialysis.

We investigated the risk factors for pulmonary hypertension (PH) in patients receiving maintenance peritoneal dialysis (MPD). A group of 180 end-stage renal disease patients (124 men and 56 women; mean age: 56.43±8.36) were enrolled in our study, which was conducted between January 2009 and June 2014. All of the patients received MPD treatment in the Dialysis Center of the Second Affiliated Hospital of Soochow University. Clinical data, laboratory indices, and echocardiographic data from these patients were collected, and follow-ups were scheduled bi-monthly. The incidence and relevant risk factors of PH were analyzed. The differences in measurement data were compared by t-test and enumeration data were compared with the χ2 test. Among the 180 patients receiving MPD, 60 were diagnosed with PH. The remaining 120 were regarded as the non-PH group. Significant differences were observed in the clinical data, laboratory indices, and echocardiographic data between the PH and non-PH patients (all P<0.05). Furthermore, hypertensive nephropathy patients on MPD showed a significantly higher incidence of PH compared with non-hypertensive nephropathy patients (P<0.05). Logistic regression analysis showed that the proportion of internal arteriovenous fistula, C-reactive protein levels, and ejection fraction were the highest risk factors for PH in patients receiving MPD. Our study shows that there is a high incidence of PH in patients receiving MPD and hypertensive nephropathy patients have an increased susceptibility to PH.

Does the presence of an arteriovenous fistula alter changes in body water following hemodialysis as determined by multifrequency bioelectrical impedance assessment?

Multifrequency bioelectrical impedance assessments (MFBIAs) aid clinical assessment of hydration status for hemodialysis (HD) patients. Many MFBIA devices are restricted to whole body measurements and as many patients dialyze using arteriovenous fistulas (AVFs), we wished to determine whether AVFs affected body water measurements. We reviewed pre- and post-HD segmental MFBIA measurements in 229 patients attending for midweek HD sessions. Up to 144 were dialyzed with a left arm AVF (L-AVF), 42 with a right arm AVF (R-AVF), and 43 by central venous access catheter (CVC). Water content and lean tissue were greater in the left compared to right arm in those patients with L-AVFs both pre and post dialysis (pre 2.1 ± 0.7 vs. 2.0 ± 0.7 L, and post 1.9 ± 0.6 vs. 1.8 ± 0.6 L and pre 2.65 ± 0.9 vs. 2.56 ± 0.8 kg, and post 2.34 ± 0.8 vs. 2.48 ± 0.8 vs. 2.34 ± 0.8 kg, respectively) and were also greater in the right compared to left arm for those patients dialyzing with R-AVFs (pre-HD 1.92 ± 0.5 vs. 1.86 ± 0.6 L and post-HD 1.79 ± 0.5 vs. 1.7 ± 0.5 L, and pre-HD 2.47 ± 0.6 vs. 2.38 ± 0.7 kg and post-HD 2.3 ± 0.74 vs. 1.28 ± 0.7 kg, respectively), all Ps < 0.05. There were no significant differences in arm volumes or composition pre or post dialysis in those dialyzing with CVCs. Segmental MFBIA detects differences in arm water and lean mass in patients with AVFs. The presence on an AVF increases the water content in the ipsilateral arm both pre and post HD. This increased water content of the fistula arm will not be detected by whole body bioimpedance devices.

Dural arteriovenous fistula (D-AVF): a rare cause of symmetrical bithalamic changes with free diffusivity changes.

We report a rare case of an encephalopathic presentation of a posterior fossa dural arteriovenous fistula with concomitant florid symmetrical bithalamic free diffusivity changes on MRI in a previously healthy individual. We describe the structural and functional imaging findings and the role of catheter angiography in diagnosis, prognostication and the timing and strategy in the management of this challenging vascular entity.

A study of prevention and regression of cardiac hypertrophy with a prolactin inhibitor in a biological model of ventricular hypertrophy caused by aorto caval fistulae in rat.

BACKGROUND: The possibility of decreasing or reverting left ventricular hypertrophy and, therefore, cardiac hypertrophy (CH) is an important medical issue. The aim of the present study was to evaluate these two possibilities with a 3-week daily dose of captopril, losartan, or bromocriptine in a preventive or corrective model. METHODS: After aorto caval fistulae (ACF) surgery on adult male Wistar rats to induce CH, animals were assigned to the preventive protocol (drug treatment began immediately after surgery) or corrective protocol (hypertrophy was allowed to develop before drug treatment). After treatments, isoproterenol was administered to half of the animals to further induce CH. The groups included the passive control, the sham-operated animals, those with ACF surgery but without drug treatment, and the 3-week treatments with captopril, losartan, or the low or high dose of bromocriptine. RESULTS: Three treatments, with captopril, losartan, or the high dose of bromocriptine, significantly impeded/reverted an increase in CH-related parameters in the preventive/corrective model compared to the surgically treated group without drug treatment. The same effect was found after isoproterenol administration. The present results show an avoidance/reversion of CH with these three treatments. Better results were found with the angiotensin converting enzyme inhibitor (captopril) than with the prolactin inhibitor (bromocriptine). CONCLUSIONS: Treatments with captopril, losartan, and the high dose of bromocriptine were effective in preventing/reversing the manifestation of CH in the preventive/corrective rat models. Further studies are needed to identify the initial mediator, the key component, and the molecular events involved in the pathogenesis of CH.

Cirsoid aneurysm of the right pre-auricular region: an unusual cause of tinnitus managed by endovascular glue embolisation.

OBJECTIVE: We report an interesting case of a right temporal pre-auricular arteriovenous fistula (cirsoid aneurysm) causing intractable tinnitus successfully managed by transarterial n-butyl cyanoacrylate glue embolisation. CASE REPORT: A 52-year-old female presented with a one-year history of tinnitus and pulsatile swelling in the right pre-auricular region. A colour Doppler ultrasound test and magnetic resonance angiography revealed a high-flow scalp arteriovenous fistula with a feeder vessel from the distal superficial temporal artery, which drained into the corresponding, dilated, tortuous vein. The patient underwent diagnostic digital subtraction angiography. This was followed by transarterial embolisation of the fistula using a 50 per cent mixture of n-butyl cyanoacrylate glue and Lipiodol®, with manual distal venous occlusion. A successful outcome was achieved with instant relief of symptoms. CONCLUSION: Cirsoid aneurysms of the facial region, an uncommon cause of tinnitus, can be effectively managed by endovascular embolisation. This treatment obviates the need for surgery, which is associated with an increased risk of complications such as scarring, deformity and bleeding.

Manejo de la lesión medular debida a una malformación arteriovenosa / Management of spinal cord lesions due to arteriovenous malformations

Las malformaciones arteriovenosas (MAV) medulares son una patología poco frecuente, comúnmente denominadas como enfermedades raras. Causan diferentes daños a nivel de la médula espinal, dependiendo del tipo de MAV. En este caso clínico, un varón de 34 años con parestesias y paraparesia progresiva es diagnosticado mediante una resonancia magnética nuclear de mielopatía aguda dorsal, precisando realizar una angiografía medular donde se descubrió la fístula arteriovenosa. El tratamiento de las MAV va dirigido a restablecer el flujo normal en la vascularización arteriovenosa medular mediante la embolización de la fístula por vía endovascular. El tratamiento rehabilitador va encaminado a conseguir la mínima discapacidad posible. En este caso, consistió en la potenciación de los diferentes grupos musculares mediante cinesiterapia y electroestimulación con el fin de conseguir su total independencia a la hora de realizar las actividades de la vida diaria

Arteriovenous malformations (AVM) in the spinal cord are uncommon. Depending on the type of AVM, different types of damage to the spinal cord are caused. In this clinical case, a 34-year-old man with paresthesia and progressive paraparesis was diagnosed with acute thoracic myelopathy using magnetic resonance imaging; angiography of the spinal cord revealed an arteriovenous fistula. Treatment of AVM aims to reestablish normal flow in the arteriovenous vascularization of the spinal cord by endovascular embolization of the fistula. Rehabilitation treatment is directed toward achieving the minimum disability possible. In this case, it consisted of strengthening the different muscle groups through kinesitherapy and electrostimulation in order to achieve their total independence when carrying out routine daily activities

[Transcatheter embolization of an inferior mesenteric arteriovenous fistula with frequent mucous diarrhea].

We report a case of inferior mesenteric arteriovenous fistula without portal hypertension or mesenteric ischemia. A 64-year-old man had developed frequent mucous diarrhea during the previous month. Colonoscopy showed highly edematous mucosa of the rectum. Barium enema demonstrated localized stricture of the same part but no evidence of malignancy. Finally we established a diagnosis by 3D-CT and selective abdominal angiography. Transcatheter arterial embolization was successfully performed. After that, his symptoms gradually improved as all abnormal findings on colonoscopy, barium enema and abdominal CT disappeared.

Treatment of renal-vascular injury by transcatheter embolization: immediate and long-term effects on renal function.

PURPOSE: To evaluate the impact of superselective embolization for treatment of renal-vascular injuries on renal function. PATIENTS AND METHODS: Between 1995 and 2004, four male patients and one female patient with a mean age of 45.4 years underwent embolization to control bleeding from renal-vascular injuries resulting from iatrogenic interventions (N = 4) or blunt abdominal trauma (N = 1). Angiography depicted a pseudoaneurysm in all patients, together with an arteriovenous fistula in one. Superselective embolization was achieved with 0.035- or 0.018-inch coils combined with a mixture of Histoacryl and Lipiodol in one patient. RESULTS: Bleeding was controlled in all patients and did not recur. No complications occurred after the procedure. Hematuria ceased within 3 days. The serum creatinine concentration returned to pre-injury values within 10 days. Embolization caused an immediate parenchymal ischemic area of 0 to 20% (mean 9%). The contrast-enhanced CT scan 6 months after the procedure revealed a parenchymal perfusion deficit of 0 to 10% (mean 5%). CONCLUSIONS: Superselective embolization resulted in permanent cessation of bleeding. Renal function was preserved in all the patients, and serum creatinine concentrations returned to the pre-injury values. Transcatheter embolization should be considered the treatment of choice in the management of renal-vascular injuries.

Effects of dietary phytoestrogens on cardiac remodeling secondary to chronic volume overload in female rats.

Previously, we demonstrated that intact female rats fed a standard rodent diet containing soybean products exhibit essentially no adverse left ventricular (LV) remodeling in response to aortocaval fistula-induced chronic volume overload. We hypothesized that phytoestrogenic compounds in the diet contributed to the female cardioprotection. To test this hypothesis, four groups of female rats were studied: sham-operated (Sham) and fistula (Fist) rats fed a diet with [P(+)] or without [P(-)] phytoestrogens. Eight weeks postfistula, systolic and diastolic cardiac function was assessed by using a blood-perfused, isolated heart preparation. High-phytoestrogen diet had no effect on body, heart, and lung weights, or cardiac function in Sham rats. Fistula groups developed LV hypertrophy, which was not reduced by dietary phytoestrogens [1,184 +/- 229 mg Fist-P(-) and 1,079 +/- 199 mg Fist-P(+) vs. 620 +/- 47 mg for combined Sham groups, P < 0.05]. Unstressed LV volume increased in Fist-P(-) rats (428 +/- 16 vs. 300 +/- 14 microl Sham, P < 0.0001), but it was not different from Sham for Fist-P(+) animals (286 +/- 17 microl). Fist-P(-) rats developed increased ventricular compliance (5.3 +/- 0.8 vs. 2.3 +/- 0.3 microl/mmHg Sham, P < 0.01), whereas Fist-P(+) rats had no change in compliance (2.8 +/- 0.4 mul/mmHg). Intrinsic ventricular contractility was maintained in the Fist-P(+) rats, but it was reduced (P < 0.001) in the Fist-P(-) rats [systolic pressure-volume slope: 1.04 +/- 0.03, 0.60 +/- 0.06, and 0.99 +/- 0.08 mmHg/microl, for Fist-P(+), Fist-P(-), and Sham, respectively]. These data indicate that dietary phytoestrogens contribute significantly to female cardioprotection against volume overload-induced adverse ventricular remodeling and that studies evaluating gender differences in cardiovascular remodeling must consider the influence of dietary phytoestrogens.

[Intrahepatic transtumoral arteriovenous fistulae (diagnosis, importance, therapeutic proposals)]. / Fístulas arteriovenosas intra-hepáticas transtumorais (diagnóstico, importância e propostas de tratamento).

The authors present the angiographic aspects of four patients having an arteriovenous transhepatic transtumoral fistula (two arterioportal and two arteriovenous). The angiographic results of the occlusion with cyanoacrylate (Hystoacryl) of the right hepatic artery in one and by the infusion of Lipiodol in two are also shown. The physiopathological characteristics of each kind of fistula are discussed and the consequences of the passage of the quimioembolizing mixture through the tumor, regarding intrahepatic abscess formation, irregular clinical results and pulmonary complications are commented. These complications make the diagnosis of a transtumoral transhepatic arteriovenous fistula, previously to the chemoembolic treatment important, even though being frequently difficult, because of the reduced caliber of the feeding artery and eventual low transfistular bloodflow. The efficient occlusion of the arterioportal fistula with Histoacryl was favourably compared to the infusion of Lipiodol, which was unable to occlude the arteriovenous fistula. The contraindication to perform chemoembolic treatment of hepatic tumors, when an intrahepatic transtumoral arteriovenous fistula is present and the embolization of the fistular feeding artery is stressed. Ultrasonography using color Doppler and sono-enhancing contrast is appointed as the ideal non-invasive means of making the diagnosis of an hepatic transtumoral fistula and makes it eligible to be the first test in the algorithm for the appraisal of hepatic tumors.

[Rendu-Osler-Weber syndrome presented paramedian thalamic and midbrain infarcts and primary medullary hemorrhage: a case report].

We reported a 41-year-old male with paramedian thalamic and midbrain infarcts due to cerebral embolism from bilateral pulmonary arterio-venous fistula and primary medullary hemorrhage. The patient had an episode of sudden onset consciousness disturbance with left Weber's syndrome (right hemiplegia and left oculomotor palsy) and vertical gaze palsy at age of 23. He noticed numbness in the left hand and the left half body under clavicular when he had got up in a morning at age 41. He had headache and left tinnitus on second and third days, and on the 3rd and 4th days, he experienced nausea. He had severe hiccup persisting from the 6th to the 13th days. The 23rd days he was admitted to our hospital. He showed dysesthesia and paresthesia in left half body under clavicular, dysesthesia in left hand and vertical gaze palsy and convergence disturbance. MRI performed on the 18th and 24th days, disclosed hyperdense mass in T1 and T2-weighted images in dorsal site of medulla, but the 70th days MRI showed no abnormal lesions. Therefore we diagnosed the high intensity mass as primary medullary hemorrhage. Cerebral angiography showed no abnormal vasculature. Many members of his family had history of sever nasal bleeding. He had skin hemangioma and mucosal hemangioma in esophagus, stomach, colon and rectum, and bilateral pulmonary arterio-venous fistula which had been operated at age 39. His mother also had skin hemangioma and pulmonary arterio-venous fistula. Therefore this family was diagnosed Rendu-Osler-Weber syndrome (hereditary hemorrhagic telangiectasia). MRI also disclosed multiple cerebral infarctions in bilateral thalamus, left cerebral peduncle and left cerebellar hemisphere.(ABSTRACT TRUNCATED AT 250 WORDS)

Total excision of a giant angiolipoma of chest wall with A-V malformation and with the use of an autotransfusion system.

An 18 year old girl suffering from a giant angiolipoma of back and chest wall with A-V malformation underwent total excision of the tumor in 4 stages. The first two stages included surgical ligation of the arterial blood supply to the tumor. In the third and fourth stages the tumor was resected with the use of an autotransfusion system. The last stage was complicated with massive bleeding and disseminated intravascular clotting. Control of bleeding was achieved by the use of autotransfusion system, right thoracotomy and massive transfusion of blood and its components. After long convalescence period associated with renal and respiratory failure the patient recovered completely without sequellae. This case demonstrates the complexity associated with the treatment of these rare tumors.

Aortocaval fistula associated with aneurysm of the abdominal aorta: current management using autotransfusion techniques.

Two patients with aortocaval fistula associated with abdominal aortic aneurysm were managed successfully using a patient care plan which includes proper monitoring of the hemodynamic state, careful dissection of the aneurysm, and return of blood loss by autotransfusion while the patient is fully anticoagulated with heparin. This unusual and serious problem in vascular surgery can be managed in an orderly and controlled fashion using these techniques.