Controversies in infective endocarditis

The infective endocarditis is defined mainly as the infection of the internal surface of the heart, affecting to the cardiac valves although it can also do it to the septos, the tendinosas cords or endocardio mural. Around the origin, the diagnosis and the treatment of the disease, a considerable controversy has taken place. In this sense, basic criteria exist that they define to the infective endocarditis; however, particular situations are appraised in which the meticulous study is essential from the patient, doing special reference to the origin agents and, more in particular, to the fungal endocarditis.     

The direct antiglobulin test in a hospital setting

To evaluate the current use of the DAT in our hospital,we reviewed the charts of all patients who had a DAT performed in our laboratory. The collected data included DAT results and a previously completed laboratory evaluation of suspected hemolytic anemia. Four hundred sixty-three DATs were performed in our laboratory from April 1999 to October 2001. The DAT was negative in 434 (93.7%) cases and positive in 29 (6.3%) cases. A complete laboratory evaluation of suspected hemolytic anemia was seen in 179 (38.7%) cases. The incidence of a positive DAT was higher in the group of patients with > 2 signs of hemolysis (4/34 cases; 11.8%) than in the group of patients with 相似文献   

Respiratory function monitoring in a child on mechanical respiratory ventilation. 2: compliance, resistance, dynamic hyperinflation, pulmonary dead-space, work of breathing

Several parameters can be used to study respiratory mechanics in children on mechanical ventilation. Compliance is a measure of the distensibility of the respiratory system. In mechanical ventilation two measures of compliance can be used. Static compliance (pulmonary distensibility) can be measured in volume modes by the application of an inspiratory pause with the respiratory system at rest (sedated patients without inspiratory effort). Dynamic compliance does not require an inspiratory pause and the respiratory system need not be at rest. Compliance can be calculated numerically or expressed graphically in the volume-pressure curve. Many respirators can calculate inspiratory and expiratory airway resistance (including endotracheal tube resistance). Several measures can be used to detect dynamic hyperinflation (intrinsic PEEP, auto-PEEP, trapped air volume) after application of an expiratory pause. The latest respirators can perform these measurements almost automatically. Work of breathing and respiratory effort can also be analyzed by measuring several parameters (pressure-time product, imposed work of breathing, P 0.1, maximum inspiratory pressure). However, these measures have not yet been standardized in children.     

One thousand seventy antibodies detected only by a 2-stage papain test: wanted and unwanted positive reactions

Despite the wide use of the antibody detection test for unexpected antibodies, controversy still remains regarding the use of enzyme-treated red blood cells. Over a 6-year period, 72,573 samples from 49,863 patients submitted for pretransfusion compatibility testing were examined for unexpected antibodies. The antibody detection tests included a low-ionic-strength solution (LISS) indirect antiglobulin test and a two-stage papain (2SP) test. One thousand and seventy of the 2267 (47%) antibodies tested by 2SP were reactive only by the 2SP test. Overall, the 2SP test detected only 0.6% of antibodies considered to be clinically significant (10 examples of anti-c and 2 examples of anti-e). The slight additional safety provided by detection of clinically-significant antibodies is overshadowed by the high number of clinically-insignificant antibodies detected by the 2SP test.     

Neuron-specific enolase,nucleotides, nucleosides,purine bases,oxypurines and uric acid concentrations in cerebrospinal fluid of children with meningitis

To determine the effects of meningitis on cerebral energy metabolism, cerebrospinal fluid concentrations of adenosine monophosphate, inosine monophosphate, inosine, adenosine, guanosine, adenine, guanine, hypoxanthine, xanthine and urate were determined by high-performance liquid chromatography, and neuron-specific enolase by an enzyme immunoassay method, in 100 children with meningitis (45 bacterial, 46 viral and nine tuberculous), aged between 1 month and 13 years, and in 160 age-matched controls. Compared with controls, patients with bacterial meningitis showed high concentrations of hypoxanthine, xanthine and urate; patients with viral meningitis showed high concentrations of inosine, guanosine, xanthine, urate and neuron-specific enolase; and patients with tuberculous meningitis showed very high concentrations of inosine, xanthine and urate. Xanthine and urate concentrations were significantly higher in patients with tuberculous meningitis than in patients with viral or bacterial meningitis. These results suggest that in the acute stage of bacterial, viral and tuberculous meningitis, neuronal energy metabolism may be altered. The measurement of cerebrospinal xanthine and uric acid concentrations may be useful for the early diagnosis of a tuberculous origin.     

Concentrations of nucleotides, nucleosides, purine bases, oxypurines, uric acid, and neuron-specific enolase in the cerebrospinal fluid of children with sepsis

To determine the effects of sepsis on cerebral energy metabolism, the cerebrospinal fluid adenosine monophosphate, inosine monophosphate, inosine, adenosine, guanosine, hypoxanthine, xanthine, and urate concentrations were determined by high-performance liquid chromatography and the neuron-specific enolase levels by means of an enzyme immunoassay method in 32 children with sepsis, without meningitis, aged between 2 months and 13 years, and in 160 age-matched controls. The septic group had significantly higher cerebrospinal fluid concentrations of inosine, adenosine, xanthine, and urate than controls. These results suggest that sepsis could provoke some degree of neuronal hypoxia and significant alterations of cerebral energy metabolism homeostasis.