Craniotomy improves outcomes for cranial subdural empyemas: computed tomography-era experience with 699 patients.

OBJECTIVE: Uncertainty regarding the best surgical management for subdural empyemas (SDEs) continues. Our unit has considered craniotomy the preferred method of surgical drainage for all cranial SDEs since 1988. We performed an analysis of our previously published, computed tomography-era, experience with 699 patients. METHODS: Two analyses of the database (1983-1997) were performed. First, analysis of the periods from 1983 to 1987 and from 1988 to 1997 was performed. Second, analysis of the composite database was performed. Outcomes were compared for possible outcome predictors by univariate analysis. Multivariate analysis was used to identify variables that contributed independently to outcomes, using stepwise discriminant analysis. RESULTS: Significant correlations between the analyzed periods with respect to outcome and type of surgery (P = 0.001) were noted. Analysis of the entire database (1983-1997) revealed a significant relationship between outcome and surgery type (P = 0.05). Pairwise comparison of limited procedures such as burr holes or craniectomies with wide-exposure surgical procedures such as primary craniotomies or procedures proceeding to full craniotomies indicated significant correlation with outcomes (P = 0.027). Reoperation and morbidity rates were increased with limited procedures. Stepwise discriminant analyses revealed that the type of surgery was correlated with outcomes (P = 0.0008, partial r(2) = 0.034). CONCLUSION: Craniotomy was determined to be the surgical procedure of choice for treatment of cranial SDEs, allowing complete evacuation of the pus and, more importantly, decompressing the underlying cerebral hemisphere. Limited procedures such as burr holes or craniectomies may be performed for patients in septic shock, for patients with parafalcine empyemas, or for children with SDEs secondary to meningitis.

Cerebral blood flow changes in rhinogenic subdural empyema and the role of hyperaemia in brain swelling.

BACKGROUND: Previous studies have demonstrated that rhinogenic subdural empyema (SDE) generally has a good prognosis. Most patients are admitted with an altered level of consciousness or significant neurological deficit, but eventually have a good outcome. It is well known that intra-operative brain swelling may occur with subdural empyema. OBJECTIVE: To define cerebral blood flow (CBF) dynamics and determine the role of cerebral hyperaemia, if any, in intracranial SDE. METHODS: CBF dynamics were assessed in five patients (mean age 13.2 +/- 2.2 years) with unilateral rhinogenic convexity SDE documented on computer tomography (CT). Regional cortical blood flow (rCBF) was measured using a thermo-coupled sensor placed on the cortex at the time of surgery. Dynamic CT scans were performed to assess cerebral blood volume (CBV) quantitatively, while transcranial Doppler ultrasonography (TCD) was used to measure cerebral blood flow velocities (CBF velocities) both pre- and post-operatively for 21 days. The opposite 'normal' hemisphere served as a control for each patient. RESULTS: Post-operative rCBF and CBF velocities in the pathological hemisphere progressively increased to plateau at 96 hours. Cerebral blood volume was increased bilaterally, but to a greater extent in the pathological hemisphere and more so in grey than white matter. These haemodynamic changes, though clinically significant did not reach statistical significance (p>0.05). CONCLUSION: Our results suggest that the accompanying brain swelling in rhinogenic SDE is a complex event, with reactive cerebral hyperaemia possibly playing neuroprotective role. Furthermore, unilateral convexity empyema causes bilateral cerebral haemodynamic changes. Future studies are necessary to define the aetiology of brain swelling in intracranial SDE.

GB virus C/hepatitis G virus infection in KwaZulu Natal, South Africa.

Sera from 70 patients on maintenance haemodialysis, 98 patients with chronic liver disease, and 232 volunteer blood donors in the province of KwaZulu Natal, South Africa, were screened for GB virus/hepatitis G virus (GBV-C/HGV) RNA and anti-E2 by reverse transcription-polymerase chain reaction (RT-PCR) and by an enzyme-linked immunosorbent assay (ELISA), respectively. GBV-C/HGV RNA was detected in 17/70 (24.3%) haemodialysis patients, 12/98 (12.2%) patients with chronic liver disease, and 44/232 (18.9%) blood donors (Africans [29/76; 38.2%]; Asians [2/52; 3.8%]; Whites [11/49; 22.4%], and "Coloureds" [persons of mixed origin; 2/55; 3.6%]). Overall (anti-E2 and/or RNA) 43.9% (43/98) of patients with chronic liver disease, 47.1% (33/70) of haemodialysis patients, and 31.9% (74/232) of blood donors (Africans [44/76; 5.9%]; Asians [5/52; 9.6%]; Whites [15/49; 30.6%], and Coloureds [9/54; 16.6%]) were exposed to GBV-C/HGV infection. There was a significant difference in the prevalence of GBV-C/HGV infection (RNA and/or anti-E2) between African blood donors and the other racial groups (P < .001), and between blood donors and haemodialysis patients (P = .02) and patients with chronic liver disease (P = .04). Anti-E2 antibodies and GBV-C/HGV RNA were almost mutually exclusive. GBV-C/HGV-infected haemodialysis patients received more transfusions (P = .03) than noninfected patients. There was no significant difference in liver biochemistry between GBV-C/HGV-infected and noninfected patients and between blood donors in each of the four racial groups. The high prevalence of GBV-C/HGV infection in blood donors and chronic liver disease patients, and the lack of elevated liver enzymes and clinical hepatitis in blood donors and haemodialysis patients, suggest that GBV-C/HGV may not be associated with liver disease.

Elevated adenosine deaminase activity in patients with HIV and tuberculous peritonitis.

OBJECTIVE: To evaluate the diagnostic potential of the ADA(T), ADA isoenzymes (ADA1 and ADA2) and the interferon-gamma (IFN-gamma) test in HIV-seropositive patients with tuberculous peritonitis. METHODS: Ascitic ADA(T), ADA1, ADA2 and IFN-gamma were prospectively evaluated in HIV-seronegative patients with tuberculous peritonitis (n = 17), HIV-seropositive patients with tuberculous peritonitis (n = 6) and in patients with cirrhosis (n = 22) and malignancy (n = 5). RESULTS: ADA(T) and ADA2 isoenzyme activities of HIV-seronegative (ADA(T) = 109 U/l; ADA2 = 94 U/l) and HIV-seropositive (ADA(T) = 109.5 U/l; ADA2 = 95.5 U/l) patients with tuberculous peritonitis, respectively, were significantly different (P < 0.001) from patients with cirrhosis (ADA(T) = 10.5 U/l; ADA2 = 8 U/l) and malignancy (ADA(T) = 13 U/l; ADA2 = 11 U/l). There was no significant difference in ADA(T) and ADA2 activities between HIV-seropositive and seronegative patients with tuberculous peritonitis. There was no significant correlation between ADA, its isoenzymes and IFN-gamma. CONCLUSIONS: The diagnosis of tuberculous peritonitis can be made by a sensitive, relatively non-invasive procedure in both HIV-seronegative and seropositive patients with minimal risk to the patient and the investigator. The diagnostic value of ADA(T) is not enhanced by measuring ADA isoenzymes or IFN-gamma.

Intracranial subdural empyemas in the era of computed tomography: a review of 699 cases.

OBJECTIVE: Intracranial empyemas are the most common form of intracranial suppuration seen in our unit and, despite modern antibiotic therapy and advanced neurosurgical and imaging facilities, these pus collections remain a formidable challenge, often resulting in significant morbidity and death. We present an analysis of our 15-year experience with this condition in the era of computed tomography. METHODS: A retrospective analysis of 4623 patients admitted with intracranial sepsis during a 15-year period (1983-1997) identified 699 patients with intracranial subdural empyemas. The inpatient notes for these patients were analyzed with respect to clinical, radiological, bacteriological, surgical, and outcome data. Statistical analyses were performed. RESULTS: The 699 intracranial subdural empyemas accounted for 15% of all admissions for intracranial sepsis during the study period. Young male patients in the second or third decade of life were most commonly affected (62%), and the mean age was 14.65+/-12.2 years. Almost all patients (96%) underwent surgery. Eighty-two percent of patients experienced good outcomes (Glasgow Outcome Scale scores of 4 or 5). A morbidity rate of 25.9% (including postoperative seizures) was noted, and 85 patients died (mortality rate, 12.2%). CONCLUSION: Intracranial subdural empyema, which is a neurosurgical emergency, is rapidly fatal if not recognized early and managed promptly. Early surgical drainage, simultaneous eradication of the primary source of sepsis, and intravenous administration of high doses of appropriate antibiotic agents represent the mainstays of treatment.

Haemodynamic response to tracheal intubation or laryngeal mask insertion in hypertensive patients.

The haemodynamic response to laryngeal mask insertion and tracheal intubation was studied in 27 hypertensive patients who underwent elective ophthalmic surgery. Both groups received alfentanil 15 micrograms/kg, thiopentone 3-4 mg/kg and vecuronium 0.1 mg/kg and were ventilated with oxygen, nitrous oxide and isoflurane for 3 minutes prior to laryngeal mask insertion or tracheal intubation. Blood pressure and heart rate decreased equally in both groups after induction of anaesthesia. Haemodynamic variables increased after tracheal intubation but were unchanged after laryngeal mask insertion (P < 0.05 for intergroup differences). Heart rate, but not blood pressure, increased above baseline levels in the tracheal intubation group. The anaesthetic technique used blunted the haemodynamic response to tracheal intubation, but completely blocked the response to laryngeal mask insertion.

Sternomental distance as the sole predictor of difficult laryngoscopy in obstetric anaesthesia.

Sternomental distance and view at laryngoscopy were documented in 523 parturients undergoing elective or emergency Caesarean section under general anaesthesia. Eighteen (3.5%) had a grade III or IV laryngoscopic view (Cormack and Lehane's classification) and were classified as potentially difficult tracheal intubations. There was a significant difference between sternomental distance in those patients with a grade III or IV laryngoscopic view compared with those with a grade I or II (13.17 (SD 1.54) cm vs 14.3 (1.49) cm; P = 0.0013). A sternomental distance of 13.5 cm or less with the head fully extended on the neck and the mouth closed provided, using discriminant analysis, the best cut-off point for predicting subsequent difficult laryngoscopy. A sternomental distance of 13.5 cm or less had a sensitivity, specificity, positive and negative predictive values of 66.7%, 71.1%, 7.6% and 98.4%, respectively. While there was no association between sternomental distance and age, weight, height or body mass index (BMI), there was a significant association between grade of laryngoscopy (III and IV) and older (P = 0.049) and heavier (P = 0.0495) mothers. The results suggest that while sternomental distance on its own may not be an adequate sole predictor of subsequent difficult laryngoscopy the measurement should be incorporated into a series of quick and simple preoperative tests.

The distribution of common intestinal nematodes along an altitudinal transect in KwaZulu-Natal, South Africa.

In order to study the effect of climate and topography on the distribution of common, intestinal nematodes in schoolchildren, changes in prevalence were investigated along an altitudinal transect from approximately 50 m above sea level (asl), near the coast, to approximately 1700 m asl, in the foothills of the Drakensberg Mountains, KwaZulu-Natal, South Africa. These changes were related to several permutations of temperature, rainfall and evaporation, using univariate and multiple regression analyses. A total of 693 primary schoolchildren aged between 7 and 15 years was examined from six communities along the 150-km transect. Changes in the prevalence of Trichuris trichiura were significantly correlated with temperature-derived variables whereas those of Ascaris lumbricoides and Necator americanus were correlated with rainfall-derived variables. A total of 17 parasite species was recovered along the transect but polyparasitism was negatively correlated with altitude.

Prognosis in posttraumatic acute renal failure is adversely influenced by hypotension and hyperkalaemia.

OBJECTIVE: To see if it is possible to predict mortality in isolated post-traumatic acute renal failure. DESIGN: Retrospective study 1984-1990 inclusive. SETTING: Teaching hospital, South Africa. SUBJECTS: Thirty-nine patients who developed isolated post-traumatic acute renal failure out of 106526 admissions for trauma. INTERVENTIONS: Standard aggressive management of traumatic injury and acute renal failure. MAIN OUTCOME MEASURE: Death. RESULTS: Fifteen of the 39 patients who developed post-traumatic acute renal failure died (39%). Blunt trauma from assaults was a major cause of acute renal failure (16/39, 41%). Hypotension and hyperkalaemia were the two main predictors of death having a mortality of 63% and 52%, respectively. CONCLUSION: Clinicians should be aware of the risks of hypotension and hyperkalaemia in injured patients. Preventive measures such as aggressive resuscitation and timely correction of serum electrolyte concentrations are essential in such patients.

Epidemiology and control of schistosomiasis mansoni in communities living on the Cuando River floodplain of East Caprivi, Namibia.

The Cuando River area of eastern Caprivi, Namibia, is highly endemic for Schistosoma mansoni whereas S. haematobium transmission, due to the scarcity of its intermediate host snail, Bulinus africanus, does not occur. Chemotherapy (6-monthly blanket treatments with praziquantel) combined with focal mollusciciding (monthly application of niclosamide) was used in a project in the area to control the disease. Although as many adults and pre-school children as possible were tested and treated, the project concentrated largely on school-age children. It took 3 years for prevalence to decline from > 80% to 20% because of a lack of proper sanitary facilities and piped water supplies and high rates of absenteeism and re-infection. However, intensity of infection decreased more rapidly, from an arithmetic mean of > 200 to < 5 eggs/g faeces. Hepatomegaly was common among school children when the project started but could be seen in only a small percentage of them after 3 years of control. Neither the bovine schistosome, S. mattheei, nor the lechwe schistosomes, S. margrebowiei and S. leiperi, were observed in the excreta of humans living in the area.

Effect of iron and pH on the survival of Vibrio cholerae in water.

Many physicochemical factors affect the survival of Vibrio cholerae in the aquatic environment. An attempt was made to study the combined effect of pH and iron on the survival of V. cholerae in water in a laboratory environment. None of the 6 strains of V. cholerae used survived at pH 5.0; survival of all strains increased with increasing pH. The effect of ferric oxide on survival was significant for V. cholerae O1 only, not for non O1 strains. The longest survival of V. cholerae non O1 was 82 d, of El Tor V. cholerae 68 d, and of classical V. cholerae 56 d.

Transcranial Doppler ultrasonography in hydrocephalic children with tuberculous meningitis.

Studies have shown a close correlation between congenital hydrocephalus (CH) and the Gosling pulsatility index (PI) determined by transcranial Doppler ultrasonography (TCD). There have not previously been similar studies in children with hydrocephalus from tuberculous meningitis (TBM), and in particular where arteritis is a prominent feature. Fifteen children from each of these two groups were prospectively examined by TCD before and after CSF diversion. Fifteen children without hydrocephalus were similarly evaluated as controls. The fall in PI following surgery was compared. The mean fall in PI in the congenital hydrocephalic group was 0.723 (SD, 0.42) as compared with 0.089 (SD, 0.16) in the TBM group (p = 0.0001). Ten of the 15 children in the TBM group had infarcts revealed by CT. In these, the PI significantly postoperatively (p = 0.004), (0.014; SD, 0.12) when compared with values obtained (0.24; SD, 0.11) in five children without infarcts. These findings indicate that the clinically relevant fall in PI following CSF diversion in children with congenital hydrocephalus does not necessarily occur in children with hydrocephalus secondary to TBM, especially when complicated by cerebral infarcts.

Risk factors for coronary heart disease in the white community of Durban.

Coronary heart disease (CHD) is the leading cause of death among the white and Indian populations of Durban. This was a community-based study of the white population of Durban, which is predominantly English-speaking. There were 396 subjects (194 men, 202 women) aged 15-69 years. A history of CHD was present in 9.3% of the subjects. The important risk factors were hypercholesterolaemia, hypertension and smoking. The minor risk factors were obesity, hypertriglyceridaemia, hyperuricaemia, a sedentary occupation and a history of CHD in the immediate family. Electrocardiograph abnormalities denoting CHD were present in 17% of subjects. A study of the major risk factors showed that 35.1% (age and sex adjusted) had at least one major risk factor at the higher level (level A) and 33.8% (age and sex adjusted) at the lower risk levels (level B). When the combination of risk factors was taken into account, 15.2% and 28% had two major risk factors, one each at levels A and B respectively. On average the percentage of men and women with one risk factor or more increased with age. A protective high-density lipoprotein/total cholesterol ratio > or = 20% was present in 53.5% of the respondents. Because of the severe nature of CHD, an intensive programme for the primary prevention of CHD risk factors should be instituted.

Operative sepsis in neurosurgery: a method of classifying surgical cases.

Neurosurgical operations have traditionally been classified along the lines of general surgical procedures. A prospective study, during an 18-month period, was undertaken in 2249 patients undergoing neurosurgical procedures to establish and evaluate a method of classifying surgical cases by the use of specific neurosurgical criteria. Patients were placed in one of five categories according to the level and type of contamination at the time of surgery. Infection included all abnormal wounds and was documented as deep when infection occurred beneath the galea (subgaleal pus, osteitis, abscess/empyema, ventriculomeningitis) and as superficial if only the scalp (including wound erythema) was involved. A statistically significant difference in the sepsis rate was found in the different categories (P < 0.0001). Of the 342 "dirty cases," 9.1% of patients developed further wound sepsis. Concomitant cerebrospinal fluid fistulae (44%), second operations (11.8%), and patients with penetrating injuries (9.2%) were the major factors implicated in sepsis in the "contaminated" category (9.7%). In the "clean contaminated" category, a sepsis rate of 6.8% was found. Prolonged surgery (longer than 4 hours) was also implicated in higher infection rates (13.4%). This study strongly supports the separation of patients who have foreign materials implanted (sepsis rate = 6.0%) from "clean" patients, essentially cases categorized as having no known risk factors that may affect sepsis, in whom a sepsis rate of 0.8% was found (P < 0.001). Importantly, surgery for the repair of so-called "clean" neural tube defects in neonates requires separate consideration. An infection rate of 14.8% existed in this subgroup. A uniform system of reporting wound abnormalities is also proposed.

The use of transcranial Doppler ultrasonography as a method of assessing intracranial pressure in hydrocephalic children.

Previous studies in children have shown a strong correlation between raised intracranial pressure (RICP) and the Gosling pulsatility index (PI) as determined by transcranial Doppler ultrasonography (TCD). This diagnostic modality can, therefore, be used as a non-invasive method for the indirect evaluation of shunt function in children with hydrocephalus. Transcranial Doppler waveform analyses were done in 15 children with hydrocephalus, before and after insertion of a ventriculo-peritoneal shunt. All had clinical evidence of raised intracranial pressure (ICP) prior to surgery. CT had demonstrated dilated ventricles and, in some, additional features of RICP. Fifteen children without clinical and CT evidence of hydrocephalus were examined in an identical manner to act as a control group. The results clearly demonstrated that TCD may be a useful, non-invasive means of assessing the need for a cerebrospinal fluid (CSF) diversionary procedure and also for follow-up and monitoring.

The association between sexually transmitted pathogens and cervical intra-epithelial neoplasia in a developing community.

OBJECTIVE--To determine the association of sexually transmitted pathogens in women with cervical intra-epithelial neoplasia (CIN). SETTING--An urban tertiary referral hospital serving a large indigent developing community. PARTICIPANTS--48 women attending a colposcopy clinic and 49 women attending a family planning clinic. METHODS--Vaginal, endocervical, rectal swab specimens and sera were collected for the detection of sexually transmitted pathogens. Cervical cytology was performed on all patients. Women attending the colposcopy clinic had confirmation of abnormal cervical cytology by colposcopic directed biopsy. RESULTS--The mean age of women with CIN (33 years) was significantly greater than that of the women without CIN (28 years) and that of the family planning group (26 years). There was a high prevalence of sexually transmitted pathogens in all women. A significantly higher prevalence of bacterial vaginosis was found in women with CIN compared to those without (50% vs 20%; p = 0.034). The human papilloma virus (HPV) was detected in 46% of women with CIN and 65% of those without CIN. Chlamydia trachomatis (21%) and Trichomonas vaginalis (39%) were detected frequently in women with CIN. C. trachomatis (14%-21%) was detected more frequently than Neisseria gonorrhoeae (3-5%) in all asymptomatic women studied. CONCLUSION--This study demonstrates a high prevalence of sexually transmitted pathogens in women with and without CIN as well as family planning clinic attenders. Bacterial vaginosis was a significant finding in women with CIN. C. trachomatis was detected in a high proportion of all women studied and found more commonly than N. gonorrhoeae. We therefore recommend that all women attending gynaecological services in a developing community be investigated and treated for sexually transmitted diseases.

The role of contralateral ventricular dilatation following surgery for intracranial mass lesions.

Contralateral ventricular dilatation (CVD) has been described as an early indicator of tentorial herniation and has been associated with increased mortality and morbidity. Following surgery for supratentorial mass lesions, ipsilateral brain swelling often causes CVD. Drainage of CVD was performed in a series of 12 patients in whom no further lesion amenable to surgery was evident and after failure of other established methods of intracranial pressure (ICP) control. In 10 of the 12 patients the ICP was brought under control with a significant reduction in ICP (p < 0.05) when compared with predrainage ICP. Midline shift was reduced in seven patients. Therefore, following successful removal of intracranial mass lesions, patients who exhibit CVD should undergo drainage as an early measure.