Necrotizing fasciitis: review of 82 cases in South Auckland.

BACKGROUND: Early recognition of necrotizing fasciitis (NF) can be difficult, but is important as infections progress rapidly and have significant mortality. The aim of this study of patients with NF was to determine the clinical characteristics at presentation, causative pathogens and subsequent clinical outcome. METHODS: We retrospectively reviewed consecutive patients with NF presenting to Middlemore Hospital from January 2000 to June 2006. RESULTS: Eighty-two patients were evaluated: 56% male, mean age 54.9 years (standard deviation 18.5), 40% Pacific Islanders. The site of infection was the lower limb in 46 (56%) patients, upper limb in 12 (15%) patients and perineum in 13 (16%) patients. Twenty-two (27%) patients were taking non-steroidal anti-inflammatory drugs, 29 (35%) had diabetes mellitus, 25 (30%) had gout and 17 (21%) had congestive heart failure. Forty-nine (60%) patients had a surgical procedure within 24 h of admission. Streptococcus pyogenes was isolated from tissue or blood cultures in 33 (40%) patients and 26 (32%) patients had polymicrobial infection. Twenty-five (30%) patients died, 17 (68%) within 72 h of admission. Independent predictors of mortality include congestive heart failure (P = 0.033) and a history of gout (P = 0.037). CONCLUSION: NF remains an important disease in our community with significant morbidity and mortality. Pacific Islanders were disproportionately represented. Early diagnosis of NF can be difficult and requires a high index of suspicion in all patients presenting with cellulitis or unexplained sepsis. Congestive heart failure and gout are independent predictors of mortality and patients with these conditions and sepsis need early assessment with more aggressive hospital triaging.

Outcome of ASA III patients undergoing day case surgery.

BACKGROUND: Day case surgery is becoming more acceptable, even for patients with complex medical conditions. Current recommendations suggest that patients who are graded as American Society of Anaesthesiologists physical status (ASA) III may be suitable for this approach. There is only a small amount of published data available to support this. We present a retrospective review of ASA III patients who had undergone day surgical procedures in our unit. METHODS: We carried out a retrospective case controlled review of 896 ASA III patients who had undergone day case procedures between January 1998 and June 2002 using the existing computerized patient information system. The system records admission rates, unplanned contact with healthcare services and post-operative complications in the first 24 h after discharge. RESULTS: We demonstrated no significant differences in unplanned admission rates, unplanned contact with health care services, or post-operative complications in the first 24 h after discharge between ASA III and ASA I or II patients. CONCLUSION: With good pre-assessment and adequate preparation ASA III patients can be treated safely in the day surgery setting.

Normal cutaneous microcirculation in gaiter zone (ulcer-susceptible skin) versus nearby regions in healthy young adults.

Skin just proximal to the medial malleolus ('gaiter' zone) is the usual site for venous ulceration in later life, whereas shin and dorsum of the foot are generally unaffected. We studied the microcirculation of these regions in 6 healthy young adults to see whether any premorbid, constitutional differences in microvascular physiology or anatomy exist between local leg sites even in normal subjects. Capillary density was assessed by capillaroscopy (native and fluorescein) and local flow by laser Doppler fluxmetry, in supine and upright positions and during reactive hyperaemia. Supine capillary densities in supramedial malleolar skin (SMMS) averaged 31038 mm(-2) (fluorescein and native count means, respectively) and was not statistically significantly different from those in the dorsum of the foot (36.0-36.2 mm(-2) or shin 30-51 mm(-2)). Dependency did not alter the counts significantly, but the fluorescein transport time from antecubital vein to capillary increased by 16-69% (SMMS 40%). In the supine position, red cell flux in SMMS was only 42-43% of the flux in skin over the shin and dorsum of the foot (p<0.04, 2-way analysis of variance) and cumulative reactive hyperaemia in SMMS was also less marked. Basal flux and reactive hyperaemia at all sites fell to closely similar levels in dependency (veni-arteriolar response). In relative terms, however, the posturally induced vasoconstriction was weaker in SMMS (flux reduction by 29% of supine value) than at other sites (reductions 61-61% of supine value). The results showed that even in young healthy legs the cutaneous microcirculation is not physiologically homogeneous, raising the possibility that constitutional factors might influence the siting of overt pathology if chronic venous insufficiency develops in later life.

Epidemiology of adverse reactions to intravascular iodinated contrast media.

Non-ionic contrast media cause fewer acute reactions than ionic media but there is insufficient data on mortality rates. An international reference centre is suggested for histological assessment of fatal reactions. Risk factors, delayed reactions, renal, neural, haemic and other miscellaneous reactions are briefly discussed.

Synergistic enhancement of histamine release from rat peritoneal mast cells by the phorbol ester 12-O-tetradecanoylphorbol 13-acetate is not reflected by corresponding changes in phospholipid turnover.

In an attempt to elucidate further the relationship between changes in phospholipid metabolism in, and histamine secretion from, purified rat peritoneal mast cells, the effects of the phorbol diester 12-O-tetradecanoylphorbol 13-acetate (TPA) on these responses in stimulated and unstimulated cells was investigated. TPA caused a dose-dependent increase in the incorporation of 32PO4(3-) into the mast cell phospholipids; phosphatidic acid (PA) and phosphatidylcholine (PC), but not phosphatidylinositol (PI). TPA synergistically enhanced histamine release from cells stimulated by anti-immunoglobulin E (IgE) and the calcium ionophore A23187, reducing its ED50 from 150 nM to 40 nM, but did not alter histamine release from cells stimulated by compound 48/80. The effect of TPA on the changes in 32PO4(3-) incorporation into phospholipids associated with the above secretagogues did not, however, correlate well with the observed effects on histamine secretion induced by the same secretagogues. These observations are discussed in relation to the known effects of phorbol esters upon both secretory processes and phospholipid metabolism in other tissues.

The hydrolysis of glycerophosphocholine by rat brain microsomes: activation and inhibition.

Experiments with glycerophosphocholine phosphodiesterase (GPC diesterase, EC 3.1.4.2.) in rat brain microsomes suggest that, although its activity is inhibited by low concentrations of calmidazolium, its dependence on Ca2+ ions is not modulated by calmodulin. The activity of glycerophosphocholine choline phosphodiesterase (choline phosphohydrolase, EC 3.1.4.38) was much lower than that of the GPC diesterase. A relatively inexpensive method for the preparation of sn-glycero-3-phospho [Me-14C]choline is described.

Activation of glycerophosphocholine phosphodiesterase in rat forebrain by Ca2+.

The highest activity of glycerophosphocholine phosphodiesterase (EC 3.1.4.2) in subcellular fractions of rat forebrain was found in the microsomal fraction though significant amounts were found in fractions containing plasma membranes. With the use of Ca(2+)/EGTA and Ca(2+)/EDTA buffers it was shown that very low concentrations of free Ca(2+) (EC(50)approx. 10(-9)m) could activate the enzyme.

The subcellular fractionation of the bovine caudate nucleus.

Two synaptosomal fractions could be obtained from bovine caudate nucleus on sucrose density gradients one of which had a much greater capacity for 'high affinity' choline uptake than the other but comparable amounts of CAT and choline kinase activity. Specific binding of QNB was widely distributed among all the subcellular fractions except the mitochondrial fraction and in quantitative terms by far the greatest amount was in the microsomal fraction. Only the microsomal fraction contained measurable amounts of glycerophosphocholine phosphodiesterase.

The current status of reactions to intravenous contrast media.

A prospective 12-month survey in 272 United Kingdom hospitals was performed and data are presented on the incidence of adverse reactions following intravenous urography, contrast CT scanning, and intravenous cholangiography. Minor and intermediate reactions are commonest in young adults, but severe and fatal reactions predominate in the older age group. There is an increased risk of severe reactions in patients with a history of allergy or previous reaction to contrast media and in patients with heart disease. The risk of severe reaction is also increased in certain ethnic groups. There appears to be an association between the incidence of severe reactions and contrast medium dose. Etiology, prevention and treatment of reactions are briefly discussed.

Choline kinase and ethanolamine kinase activity in the cytosol of nerve endings from rat forebrain.

Both choline kinase and ethanolamine kinase are present in the cytosol of nerve endings prepared from rat brain are the products of their action, phosphocholine (84 nmol/g fresh wt. of brain) and phosphoethanolamine (190 nmol/g fresh wt. of brain). In contrast with the enzymes from the cytosol of whole brain, both are as equally active at pH 7.5 as 9.0. Determination of kinase activity in membrane-containing tissue samples at pH9 gives low values because of the activity of alkaline phosphatase. Choline kinase, but not ethanolamine kinase, requires Mg2+ in excess of that required for the formation of the MgATP complex and is inhibited by an excess of free ATP. The Km for choline is 2.6mM and for ethanolamine is 2.2mM. The differing requirements for ATP and Mg2+ and the inhibition of choline kinase, but not ethanolamine kinase, by hemicholinium-3 suggest either the presence of two separate enzymes or two different active sites on the same enzyme.