Determinants of self-efficacy in patients with Parkinson's disease.

BACKGROUND: Self-efficacy is the individual's assessment of his or hers ability to complete a specific task successfully and has been closely related to self-management and quality of life in several diseases. OBJECTIVE: To investigate self-efficacy in a population of Parkinson's disease (PD) patients in Mexico and study the factors that are associated with this measure. METHODS: We carried out a cross-sectional observational study involving patients with PD in an outpatient neurology clinic in Mexico, using the following instruments: Spanish version of the Chronic Disease Self-Efficacy Scale (CDSES), Quality of Life Questionnaire PDQ-8, Movement Disorders Society-Unified Parkinson's disease Rating Scale (MDS-UPDRS), Montreal Cognitive Assessment (MoCA), and Non-Motor Symptom Scale (NMSS). Clinical and demographic variables were also recorded. RESULTS: We included 73 patients with a mean age of 65 years and most patients were male. Patients with lower CDSES scores (<7.75) had worse scores in MDS-UPDRS, NMSS, and PDQ-8 scales. CDSES scores were significantly correlated with MDS-UPDRS Part I (r=-0.497, p=<0.001), Part II (r= -0.271, p=0.020), Part III (r=-0.304, p=<0.001), PDQ-8 (r=-0.472, p=<0.001), and NMSS (r=-0.504, p=<0.001). Furthermore, when assessing the simultaneous effect of covariates associated with CDSES score, only Mood/Apathy domain of NMSS was significant (beta= -0.446, t= -3.807, p= 0.012). CONCLUSIONS: PD patients with lower self-efficacy scores had worse motor and non-motor symptomatology and quality of life. Mood/Apathy disorders were negatively associated with self-efficacy and contributed significantly to this measure.

Determinants of self-efficacy in patients with Parkinson's disease / Determinantes de autoeficacia en pacientes con enfermedad de Parkinson

ABSTRACT Background: Self-efficacy is the individual's assessment of his or hers ability to complete a specific task successfully and has been closely related to self-management and quality of life in several diseases. Objective: To investigate self-efficacy in a population of Parkinson's disease (PD) patients in Mexico and study the factors that are associated with this measure. Methods: We carried out a cross-sectional observational study involving patients with PD in an outpatient neurology clinic in Mexico, using the following instruments: Spanish version of the Chronic Disease Self-Efficacy Scale (CDSES), Quality of Life Questionnaire PDQ-8, Movement Disorders Society-Unified Parkinson's disease Rating Scale (MDS-UPDRS), Montreal Cognitive Assessment (MoCA), and Non-Motor Symptom Scale (NMSS). Clinical and demographic variables were also recorded. Results: We included 73 patients with a mean age of 65 years and most patients were male. Patients with lower CDSES scores (<7.75) had worse scores in MDS-UPDRS, NMSS, and PDQ-8 scales. CDSES scores were significantly correlated with MDS-UPDRS Part I (r=-0.497, p=<0.001), Part II (r= -0.271, p=0.020), Part III (r=-0.304, p=<0.001), PDQ-8 (r=-0.472, p=<0.001), and NMSS (r=-0.504, p=<0.001). Furthermore, when assessing the simultaneous effect of covariates associated with CDSES score, only Mood/Apathy domain of NMSS was significant (beta= -0.446, t= -3.807, p= 0.012). Conclusions: PD patients with lower self-efficacy scores had worse motor and non-motor symptomatology and quality of life. Mood/Apathy disorders were negatively associated with self-efficacy and contributed significantly to this measure.

RESUMEN Antecedentes: La autoeficacia es la autoevaluación de un individuo sobre su capacidad para completar una tarea con éxito y se ha relacionado con automanejo y calidad de vida en otras enfermedades. Objetivo: Investigar la autoeficacia en una población de pacientes con enfermedad de Parkinson (EP) en México y estudiar factores asociados con esta medida. Métodos: Realizamos un estudio observacional transversal con pacientes con EP en una clínica de neurología en México. Se registraron datos demográficos y escalas que evalúan la función motora (MDS-UPDRS), no motora (NMSS) y cognitiva (MoCA), así como la calidad de vida (PDQ-8). Para valorar autoeficacia se utilizó la versión en español de la Escala de autoeficacia de enfermedades crónicas (CDSES). Resultados: Se incluyeron 73 pacientes, con una edad media de 65 años y la mayoría eran hombres. Pacientes con puntajes CDSES más bajos (<7.75) tuvieron peores puntajes en las escalas MDS-UPDRS, NMSS y PDQ-8. Las puntuaciones de CDSES se correlacionaron significativamente con la escala MDS-UPDRS Parte I (r=-0.497, p=<0.001), Parte II (r= -0.271, p=0.020), Parte III (r=-0.304, p=<0.001), PDQ-8 (r= -0.472, p=<0.001), y NMSS (r=-0.504, p=<0.001). Al evaluar el efecto simultáneo de covariables asociadas con la escala CDSES, solo el dominio estado de ánimo/apatía del NMSS resultó significativo (Beta = -0.449, t = -3.783, p = <0.001). Conclusiones: Los pacientes con menores puntajes de autoeficacia tienen peor calidad de vida y sintomatología motora y no motora. Los trastornos del estado de ánimo contribuyen negativamente a la autoeficacia.

[Impacto en el desenlace funcional en pacientes con ictus: experiencia de una unidad de cuidados neurovasculares].

Background and objective: Neurovascular care units (NCU) have a positive impact on the functional prognosis of stroke patients. The effectiveness of NCUs in Mexico has not been evaluated. Our objective was to determine the impact of an NCU in a third-level academic hospital in northeastern of Mexico. Method: We performed a prospective observational, analytic cohort study. The population was divided into two periods: the first one consisted of those patients admitted before the implementation of the NCU (2008-2010), and the second period consisted of patients admitted after the implementation of the UCN (2010-2014). Functional status was assessed with the modified Rankin scale at discharge and 3 months. Results and conclusions: 598 patients were included (period 1: 246; period 2: 352). Patients in period 2 had a higher deep venous thrombosis prophylaxis (odds ratio [OR]: 3.235; 95 % confidence interval [95 % CI]: 2.18-4.80; p = 0.01), a shorter hospital stay (OR: 0.42; 95 % CI: 0.29-0.62; p = 0.01) and less severe disability (Rankin ≥ 3) at 3 months of follow-up (OR: 0.42; 95 % CI: 0.29-0.62; p = 0.01). The implementation of an NCU in a third-level academic hospital improved the functional outcome at 3 months and decreased the days of in-hospital stay of patients with stroke.

Antecedentes y objetivo: Las unidades de cuidados neurovasculares (UCN) impactan favorablemente en el pronóstico funcional del paciente con ictus en comparación con las salas de internamiento general. La efectividad de las UCN en México no ha sido evaluada. Nuestro objetivo fue determinar el impacto que tiene una UCN en un hospital académico de tercer nivel del noreste de México. Método: Estudio de cohorte prospectivo, observacional y analítico. La población fue dividida en dos periodos: el primero consistió en aquellos pacientes ingresados antes de la implementación de la UCN (2008-2010), y el segundo consistió en pacientes ingresados posterior a la implementación de la UCN (2010-2014). Se evaluó el estado funcional al egreso y a los 3 meses. Resultados y conclusiones: Se incluyeron 598 pacientes (periodo 1: 246; periodo 2: 352). En el periodo 2 se incrementó la profilaxis de trombosis venosa profunda (razón de momios [RM]: 3.235; intervalo de confianza del 95 % [IC 95 %]: 2.18-4.80; p = 0.01) y se redujeron la estancia hospitalaria (RM: 0.42; IC 95 %: 0.29-0.62; p = 0.01) y la discapacidad funcional grave (Rankin ≥ 3) a los 3 meses de seguimiento (RM: 0.42; IC 95 %: 0.29-0.62; p = 0.01). La implementación de una UCN mejoró el desenlace funcional a 3 meses y disminuyó los días de estancia intrahospitalaria de pacientes con ictus.

Mean platelet volume in the differential diagnosis of tuberculous and bacterial meningitis.

INTRODUCTION: Mean platelet volume (MPV) has been shown to reflect the inflammatory burden in different inflammatory and autoimmune diseases. Our objective was to analyze the MPV in patients with tuberculous (TBM) and bacterial meningitis (BM). METHODOLOGY: The demographic and clinical data of 73 consecutive patients that presented with either BM (n = 35) or TBM (n = 38) were retrospectively analyzed, as well as that of 28 age- and sex-matched controls. RESULTS: MPV was 8.78±1.58 fL in patients with BM and 6.42±1.39 fL in the TBM group (p < 0.05). In the control group, MPV was 7.4±0.66 fL, significantly higher and lower when compared with TBM and BM, respectively. MPV was significantly associated with diagnosis (adjusted OR: 5.15, 95% CI: 1.090-23.7; p = 0.03). With the optimal cut-off value of 7.62 fL, MPV had 82% sensibility and 78% specificity for the differential diagnosis of TBM versus BM. Lower platelet counts, higher serum creatinine, higher white blood cell counts, and higher blood-cerebrospinal fluid glucose ratio were also predictive of BM. CONCLUSIONS: Platelet counts were lower and MPV was higher in patients with BM compared to patients with TBM.  Platelet indices, available in routine bloodwork, could be useful in the early differential diagnosis of these entities.

Acute toluene intoxication--clinical presentation, management and prognosis: a prospective observational study.

BACKGROUND: Toluene is one of the most widely abused inhaled drugs due to its acute neurologic effects including euphoria and subsequent depression. However, dangerous metabolic abnormalities are associated to acute toluene intoxication. It has been previously reported that rhabdomyolysis and acute hepatorenal injury could be hallmarks of the condition, and could constitute risk factors for poor outcomes. The objective was to describe the clinical presentation, to characterize the renal and liver abnormalities, the management and prognosis associated to acute toluene intoxication. METHODS: We prospectively assessed 20 patients that were admitted to a single center's emergency department from September 2012 to June 2014 with clinical and metabolic alterations due to acute toluene intoxication. RESULTS: The main clinical presentation consisted of weakness associated to severe hypokalemia and acidosis. Renal glomerular injury (proteinuria) is ubiquitous. Biliary tract injury (alkaline phosphatase and gamma-glutamyl transpeptidase elevations) disproportional to hepatocellular injury is common. Rhabdomyolysis occurred in 80% of patients, probably due to hypokalemia and hypophosphatemia. There were three deaths, all female, and all associated with altered mental status, severe acidosis, hypokalemia and acute oliguric renal failure. The cause of death was in all cases due to cardiac rhythm abnormalities. CONCLUSION: The hallmarks of acute toluene intoxication are hypokalemic paralysis and metabolic acidosis. Liver injury and rhabdomyolysis are common. On admission, altered mental status, renal failure, severe acidemia and female gender (not significant in our study, but present in all three deaths) could be associated with a poor outcome, and patients with these characteristics should be considered to be treated in an intensive care unit.

Clinical features and outcome of mucormycosis.

Mucormycosis (MCM) is a life-threatening infection that carries high mortality rates despite recent advances in its diagnosis and treatment. The objective was to report 14 cases of mucormycosis infection and review the relevant literature. We retrospectively analyzed the demographic and clinical data of 14 consecutive patients that presented with MCM in a tertiary-care teaching hospital in northern Mexico. The mean age of the patients was 39.9 (range 5-65). Nine of the patients were male. Ten patients had diabetes mellitus as the underlying disease, and 6 patients had a hematological malignancy (acute leukemia). Of the diabetic patients, 3 had chronic renal failure and 4 presented with diabetic ketoacidosis. All patients had rhinocerebral involvement. In-hospital mortality was 50%. All patients received medical therapy with polyene antifungals and 11 patients underwent surgical therapy. Survivors were significantly younger and less likely to have diabetes than nonsurvivors, and had higher levels of serum albumin on admission. The clinical outcome of patients with MCM is poor. Uncontrolled diabetes and age are negative prognostic factors.

Hepatic ischemia/reperfusion injury is diminished by atorvastatin in Wistar rats.

BACKGROUND AND AIMS: Temporal occlusion of the hepatoduodenal ligament (HDL) is often used during liver surgeries in order to reduce blood loss, resulting in ischemia/reperfusion injury (I/R). The aim of the study was to investigate the effects of atorvastatin (ATOR) on hepatic I/R injury and on serum levels of tumor necrosis factor-alpha (TNF-α), endothelin-1 (ET-1), antithrombin III (ATIII) and intracellular adhesion molecule-1 (ICAM-1). METHODS: Liver ischemia was induced in Wistar rats by clamping the HDL for 60 min, followed by either 60 or 180 min reperfusion. Rats received either vehicle or 10 mg/kg ATOR before hepatic I/R. Control group received sham surgery. Livers were examined for histological damage and serum AST, ALT, TNF-α, ET-1, ATIII and ICAM-1 concentrations were measured. RESULTS: After I/R, AST and ALT were significantly elevated, ATIII levels were significantly depleted, both TNF-α and ICAM-1 levels increased and ET-1 was significantly elevated (at 180 min). ATOR pretreatment attenuated these alterations and diminished histological injury scores. CONCLUSIONS: Our results show that ATOR protects the liver from I/R injury.

1,25-dihydroxyvitamin D and PTHrP mediated malignant hypercalcemia in a seminoma.

BACKGROUND: Seminomas have been rarely associated with malignant hypercalcemia. The responsible mechanism of hypercalcemia in this setting has been described to be secondary to 1,25-dihydroxyvitamin D secretion. The relationship with PTHrP has not been determined or studied.The aim of this study is to describe and discuss the case and the pathophysiological mechanisms involved in a malignant hypercalcemia mediated by 1,25-dihydroxyvitamin D and PTHrP cosecretion in a patient with seminoma. CASE PRESENTATION: A 35-year-old man was consulted for assessment and management of severe hypercalcemia related to an abdominal mass. Nausea, polyuria, polydipsia, lethargy and confusion led him to the emergency department. An abdominal and pelvic enhanced CT confirmed a calcified pelvic mass, along with multiple retroperitoneal lymphadenopathy. Chest x-ray revealed "cannon ball" pulmonary metastases. The histopathology result was consistent with a seminoma. Serum calcium was 14.7 mg/dl, PTH was undetectable, 25-dihydroxyvitamin D was within normal values and PTHrP and 1,25-dihydroxyvitamin were elevated (35.0 pg/ml, and 212 pg/ml, respectively). After the first cycle of chemotherapy with bleomycin, etoposide and cisplatin, normocalcemia was restored. Both PTHrP and 1,25-dihydroxyvitamin D, dropped dramatically to 9.0 pg/ml and 8.0 pg/ml, respectively. CONCLUSION: The association of seminoma and malignant hypercalcemia is extremely rare. We describe a case of a patient with a seminoma and malignant hypercalcemia related to paraneoplastic cosecretion of 1,25-dihydroxyvitamin D and PTHrP. After successful chemotherapy, calcium, PTHrP and 1,25-Dihydroxyvitamin D returned to normal values.

Remote ischemic preconditioning as treatment for non-ischemic gastrointestinal disorders: beyond ischemia-reperfusion injury.

Common gastrointestinal diseases such as radiation enteritis (RE), acute pancreatitis, inflammatory bowel diseases (IBD) and drug-induced hepatotoxicity share pathophysiological mechanisms at the molecular level, mostly involving the activation of many pathways of the immune response, ultimately leading to tissue injury. Increased oxidative stress, inflammatory cytokine release, inflammatory cell infiltration and activation and the up-regulation of inflammatory transcription factors participate in the pathophysiology of these complex entities. Treatment varies in each specific disease, but at least in the cases of RE and IBD immunosuppressors are effective. However, full therapeutic responses are not always achieved. The pathophysiology of ischemia-reperfusion (IR) injury shares many of these mechanisms. Brief and repetitive periods of ischemia in an organ or limb have been shown to protect against subsequent major IR injury in distant organs, a phenomenon called remote ischemic preconditioning (RIP). This procedure has been shown to protect the gut, pancreas and liver by modulating many of the same inflammatory mechanisms. Since RIP is safe and tolerable, and has shown to be effective in some recent clinical trials, I suggest that RIP could be used as a physiologically relevant adjunct treatment for non-ischemic gastrointestinal inflammatory conditions.

Temporal relationship of serum markers and tissue damage during acute intestinal ischemia/reperfusion.

OBJECTIVE: It is essential to identify a serological marker of injury in order to study the pathophysiology of intestinal ischemia reperfusion. In this work, we studied the evolution of several serological markers after intestinal ischemia reperfusion injury in rats. The markers of non-specific cell damage were aspartate aminotransferase, alanine aminotransaminase, and lactic dehydrogenase, the markers of inflammation were tumor necrosis factor alpha, interleukin-6, and interleukin-1 beta, and the markers of intestinal mucosal damage were intestinal fatty acid binding protein and D-lactate. We used Chiús classification to grade the histopathological damage. METHODS: We studied 35 Wistar rats divided into groups according to reperfusion time. The superior mesenteric artery was clamped for 30 minutes, and blood and biopsies were collected at 1, 3, 6, 12, 24, and 48 hours after reperfusion. We plotted the mean ± standard deviation and compared the baseline and maximum values for each marker using Student's t-test. RESULTS: The maximum values of interleukin-1 beta and lactic dehydrogenase were present before the maximal histopathological damage. The maximum tumor necrosis factor alpha and D-lactate expressions coincided with histopathological damage. Alanine aminotransaminase and aspartate aminotransferase had a maximum expression level that increased following the histopathological damage. The maximum expressions of interluken-6 and intestinal fatty acid binding protein were not significantly different from the Sham treated group. CONCLUSION: For the evaluation of injury secondary to acute intestinal ischemia reperfusion with a 30 minute ischemia period, we recommend performing histopathological grading, quantification of D-lactate, which is synthesized by intestinal bacteria and is considered an indicator of mucosal injury, and quantification of tumor necrosis factor alpha as indicators of acute inflammation three hours after reperfusion.

Temporal relationship of serum markers and tissue damage during acute intestinal ischemia/reperfusion

OBJECTIVE: It is essential to identify a serological marker of injury in order to study the pathophysiology of intestinal ischemia reperfusion. In this work, we studied the evolution of several serological markers after intestinal ischemia reperfusion injury in rats. The markers of non-specific cell damage were aspartate aminotransferase, alanine aminotransaminase, and lactic dehydrogenase, the markers of inflammation were tumor necrosis factor alpha, interleukin-6, and interleukin-1 beta, and the markers of intestinal mucosal damage were intestinal fatty acid binding protein and D-lactate. We used Chiús classification to grade the histopathological damage. METHODS: We studied 35 Wistar rats divided into groups according to reperfusion time. The superior mesenteric artery was clamped for 30 minutes, and blood and biopsies were collected at 1, 3, 6, 12, 24, and 48 hours after reperfusion. We plotted the mean ± standard deviation and compared the baseline and maximum values for each marker using Student's t-test. RESULTS: The maximum values of interleukin-1 beta and lactic dehydrogenase were present before the maximal histopathological damage. The maximum tumor necrosis factor alpha and D-lactate expressions coincided with histopathological damage. Alanine aminotransaminase and aspartate aminotransferase had a maximum expression level that increased following the histopathological damage. The maximum expressions of interluken-6 and intestinal fatty acid binding protein were not significantly different from the Sham treated group. CONCLUSION: For the evaluation of injury secondary to acute intestinal ischemia reperfusion with a 30 minute ischemia period, we recommend performing histopathological grading, quantification of D-lactate, which is synthesized by intestinal bacteria and is considered an indicator of mucosal injury, and quantification of tumor necrosis ...

Takayasu's arteritis and posterior reversible encephalopathy syndrome: a case-based review.

Autoimmune vasculitides can have diverse neurological manifestations, including posterior reversible encephalopathy syndrome (PRES). Takayasu's arteritis (TA) is an uncommon vasculitis rarely associated with PRES. Common clinical features of TA include hypertension, audible arterial bruits, absence of peripheral pulses, claudication of the extremities, reduced blood pressure in one or both arms, and angiographic abnormalities. PRES has been mostly associated with severe hypertension, endothelial injury, and conditions such as renal disease, immunosuppressive medication use, and rheumatologic diseases. Headaches, seizures, and altered mental status are the main clinical features as well as characteristic findings in magnetic resonance imaging. TA frequently presents with hypertension and is associated with endothelial injury, making this entity an ideal setting for the development of PRES. We report the case of a 17-year-old female who presented to the emergency department with severe hypertension, headache, and seizures. Magnetic resonance imaging findings were suggestive of PRES. She had absent pulses in the right upper extremity, abdominal bruits, and angiographic findings included subclavian and renal artery stenoses. The diagnosis of TA was made, and she responded well to treatment. We found ten additional cases of TA and PRES in the literature. All patients were females under the age of 40, had renovascular hypertension, and presented with headaches and seizures. Current literature relevant to this rare association is presented and discussed.

Isolated rheumatoid arthritis-associated cerebral vasculitis: a diagnostic challenge.

Central nervous system involvement in rheumatoid arthritis is uncommon. In order of frequency, published cases have reported rheumatoid nodules, meningeal vasculitis, and cerebral vasculitis (CV). The frequency of vasculitic cerebral involvement in rheumatoid arthritis is unknown. However, it is known that it is more common in patients with seropositive, long-standing rheumatoid arthritis, and in those with concomitant systemic vasculitis. We report the case of a 47-year-old woman with an 11-year history of seropositive rheumatoid arthritis without any extra-articular manifestations, with the exception of secondary Sjogren's syndrome, presenting with mental status changes and tonic-clonic seizures as symptoms of isolated CV. Magnetic resonance imaging (T2) showed hyperintense white-matter lesions in the frontal and temporal lobes, as well as in the hippocampus and cerebellum. Transcranial Doppler ultrasound findings were consistent with CV. Other differential diagnoses were ruled out. The patient responded favorably to methylprednisolone and intravenous gammaglobulin therapy.

Arachidonic acid derivatives and their role in peripheral nerve degeneration and regeneration.

After peripheral nerve injury, a process of axonal degradation, debris clearance, and subsequent regeneration is initiated by complex local signaling, called Wallerian degeneration (WD). This process is in part mediated by neuroglia as well as infiltrating inflammatory cells and regulated by inflammatory mediators such as cytokines, chemokines, and the activation of transcription factors also related to the inflammatory response. Part of this neuroimmune signaling is mediated by the innate immune system, including arachidonic acid (AA) derivatives such as prostaglandins and leukotrienes. The enzymes responsible for their production, cyclooxygenases and lipooxygenases, also participate in nerve degeneration and regeneration. The interactions between signals for nerve regeneration and neuroinflammation go all the way down to the molecular level. In this paper, we discuss the role that AA derivatives might play during WD and nerve regeneration, and the therapeutic possibilities that arise.

Clinical presentation and management in acute toluene intoxication: a case series.

CONTEXT: Toluene inhalation is a common form of drug abuse throughout the world. Acute toluene toxicity causes neurological changes as well as various metabolic alterations. Hypokalemic paralysis and renal failure are life-threatening complications. OBJECTIVE: To identify the clinical and metabolic alterations associated with toluene intoxication. MATERIALS AND METHODS: We retrospectively analyzed the records of 22 patients that were admitted to a single center's emergency department from 2006 to 2012 with clinical and metabolic alterations due to toluene inhalation. RESULTS: Of the 22 patients, 77% were male and mean age was 23.5 years (range: 17-30). The main clinical presentation was weakness associated to severe hypokalemia. Severe metabolic acidosis was found in 20 patients. Renal tubular acidosis was diagnosed in five patients. The patients responded to supportive measures and aggressive potassium repletion. Prognosis was generally good. CONCLUSION: Toluene inhalation is associated with various severe metabolic alterations. Treatment guidelines are needed considering the frequency of toluene inhalation in the population.

Wernicke encephalopathy presenting in a patient with severe acute pancreatitis.

CONTEXT: Acute pancreatitis can lead to prolonged fasting and malnutrition. Many metabolic changes, including thiamine deficiency, may lead to the well know pancreatic encephalopathy. In this condition however the thiamine deficiency is rarely suspected. CASE REPORT: We report the case of a 17-year-old woman with severe acute pancreatitis who developed mental status changes and ophthalmoplegia. A magnetic resonance image showed hyperintensive signals in periventricular areas, medial thalamus, and mammillary bodies, findings consistent with the diagnosis of Wernicke encephalopathy. Thiamine treatment reversed neurological complications. CONCLUSION: Wernicke encephalopathy secondary to thiamine deficiency should be considered as a possible cause of acute mental status changes in patients with acute pancreatitis and malnutrition. Prophylactic doses of thiamine could be considered in susceptible patients.

Solitary Apical Lung Mass in a Patient With Cervical Cancer.

We present the case of a 40 years old female presenting with a solitary apical lung mass, associated Horner syndrome and evidence of medullary compression. Although she had a history of cervical cancer, a primary lung tumor was suspected. Tissue biopsy confirmed cervical cancer metastasis, highlighting the fact that although metastasis usually presents as multiple lung nodules, solitary lesions can be the presenting sign.