Pathways to diabetic limb amputation. Basis for prevention

We defined the causal pathways responsible for 80 consecutive initial lower-extremity amputations to an extremity in diabetic patients at the Seattle Veterans Affairs Medical Center over a 30-mo interval from 1984 to 1987. Causal pathways, either unitary or composed of various combinations of seven potential causes (i.e., ischemia, infection, neuropathy, faulty wound healing, minor trauma, cutaneous ulceration, gangrene), were determined empirically after a synthesis by the investigators of various objective and subjective data. Estimates of the proportion of amputations that could be ascribed to each component cause were calculated. Twenty-three unique causal pathways to diabetic limb amputation were identified. Eight frequent constellations of component causes resulted in 73% of the amputations. Most pathways were composed of multiple causes, with only critical ischemia from acute arterial occlusions responsible for amputations as a singular cause. The causal sequence of minor trauma, cutaneous ulceration, and wound-healing failure applied to 72% of the amputations, often with the additional association of infection and gangrene. We specified precise criteria in the definition of causal pathway to permit estimation of the cumulative proportion of amputations due to various causes. Forty-six percent of the amputations were attributed to ischemia, 59% to infection, 61% to neuropathy, 81% to faulty wound healing, 84% to ulceration, 55% to gangrene, and 81% to initial minor trauma. An identifiable and potentially preventable pivotal event, in most cases an episode involving minor trauma that caused cutaneous injury, preceded 69 to 80 amputations. Defining causal pathways that predispose to diabetic limb amputation suggests practical interventions that may be effective in preventing diabetic limb loss.

Ischaemic colitis

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Randomised trial of laparoscopic versus open cholecystectomy for acute and gangrenous cholecystitis

BACKGROUND

Laparoscopic cholecystectomy (LC) has become the treatment of choice for elective cholecystectomy, but controversy persists over use of this approach in the treatment of acute cholecystitis. We undertook a randomised comparison of the safety and outcome of LC and open cholecystectomy (OC) in patients with acute cholecystitis.

METHODS

63 of 68 consecutive patients who met criteria for acute cholecystitis were randomly assigned OC (31 patients) or LC (32 patients). The primary endpoints were hospital mortality and morbidity, length of hospital stay, and length of sick leave from work. Analysis was by intention to treat. Suspected bile-duct stones were investigated by preoperative endoscopic retrograde cholangiography (LC group) or intraoperative cholangiography (OC group).

FINDINGS

The two randomised groups were similar in demographic, physical, and clinical characteristics. 48% of the patients in the OC group and 59% in the LC group were older than 60 years. 13 patients in each group had gangrene or empyema, and one in each group had perforation of the gallbladder causing diffuse peritonitis. Five (16%) patients in the LC group required conversion to OC, in most because severe inflammation distorted the anatomy of Calot's triangle. There were no deaths or bile-duct lesions in either group, but the postoperative complication rate was significantly (p=0.0048) higher in the OC than in the LC group: seven (23%) patients had major and six (19%) minor complications after OC, whereas only one (3%) minor complication occurred after LC. The postoperative hospital stay was significantly shorter in the LC than the OC group (median 4 [IQR 2-5] vs 6 [5-8] days; p=0.0063). Mean length of sick leave was shorter in the LC group (13.9 vs 30.1 days; 95% CI for difference 10.9-21.7).

INTERPRETATION

Even though LC for acute and gangrenous cholecystitis is technically demanding, in experienced hands it is safe and effective. It does not increase the mortality rate, and the morbidity rate seems to be even lower than that in OC. However, a moderately high conversion rate must be accepted.

Reperfusion injury after intestinal ischemia

OBJECTIVE

Review the histologic and pathophysiologic alterations seen after intestinal ischemia and reperfusion.

DATA SOURCE

Current literature review.

STUDY SELECTION

The most pertinent, current, and representative articles describing results from both animal and human investigations are utilized and discussed.

DATA SYNTHESIS

Postischemic intestinal tissue damage appears to be due to the formation of oxygen radicals and the activation of phospholipase A2. The initial source of oxygen radicals seems to be the hypoxanthine-xanthine oxidase system. Oxygen radicals react directly with poly-unsaturated fatty acids, leading to lipid peroxidation within the cell membranes. Indirectly, the radicals trigger the accumulation of neutrophils within the affected tissue initiating inflammatory processes that lead to severe mucosal lesions. Similarly, phospholipase A2 also initiates postischemic mucosal lesions. Phospholipase A2 is a hydrolytic enzyme capable of increasing formation of cytotoxic lysophospholipids within the tissue. Enhanced activity of phospholipase A2 also stimulates the production of prostaglandins and leukotrienes. Various substances (superoxide dismutase, catalase, dimethyl sulfoxide, allopurinol, and deferoxamine, etc.) are able to detoxify oxygen radicals or inhibit the mechanisms leading to their enhanced generation, thus attenuating the postischemic lesions of the mucosa.

CONCLUSIONS

Oxygen radicals and the activation of phospholipase A2 during reperfusion seem to be instrumental for the development of hemorrhagic mucosal lesions after intestinal ischemia. Radical scavengers and phospholipase A2 inhibitors may prevent reperfusion damage of the intestine, even when the treatment starts during ischemia but before reperfusion.

Percutaneous transluminal angioplasty of the arteries of the lower limbs: a 5 year follow-up

A total of 482 percutaneous transluminal angioplasties (PTAs) of the arteries of the lower limbs were performed in 411 patients between 1977 and 1983. The 5 year patency rate, calculated by the life table method, was 83% for iliac and 58% for femoropopliteal PTA. Clinical improvement after the procedure was confirmed by a significant drop of the arm-ankle pressure difference: 48 +/- 5 mm Hg before vs 17 +/- 5 mm Hg 2 years after iliac PTA (p less than .01) and 73 +/- 5 mm Hg before vs 28 +/- 6 mm Hg after femoropopliteal PTA (p less than .01). The majority of reocclusions occurred within the first year after angioplasty. Patients with stenoses or occlusions of less than 3 cm had a favorable long-term patency rate of 74%. Conversely, patients with femoropopliteal occlusions presenting with pain at rest, diabetes, occlusions of greater than 3 cm, or poor distal runoff had an elevated rate of reocclusion. Complications, which occurred in 8% of the patients in whom PTA was attempted, included local hemorrhage, dissection, embolism, and spasm necessitating surgical intervention in 2%. No deaths or amputations were a direct consequence of PTA. PTA of arteries of the lower limbs may thus be regarded as a valid complementary treatment to vascular surgery in patients with occlusive disease of the peripheral arteries.

A retrospective study on malignant neoplasms of bladder, lung and liver in blackfoot disease endemic area in Taiwan

A total of 69 bladder cancer, 76 lung cancer and 59 liver cancer deceased cases and 368 alive community controls group-matched on age and sex were studied to evaluate the association between high-arsenic artesian well water and cancers in the endemic area of blackfoot disease (BFD), a unique peripheral vascular disease related to continuous arsenic exposure. According to a standardized structured questionnaire, information on risk factors was obtained through proxy interview of the cases and personal interview of the controls. A positive dose-response relationship was observed between the exposure to artesian well water and cancers of bladder, lung and liver. The age-sex-adjusted odds ratios of developing bladder, lung and liver cancers for those who had used artesian well water for 40 or more years were 3.90, 3.39, and 2.67, respectively, as compared with those who never used artesian well water. Multiple binary logistic regression analyses showed that the dose-response relationships and odds ratios remained much the same while other risk factors were further adjusted.

CT findings in acute gangrenous cholecystitis

OBJECTIVE

The purpose of this study was to determine the CT findings in acute gangrenous cholecystitis.

MATERIALS AND METHODS

Four observers retrospectively reviewed CT scans in 75 patients (23 with acute gangrenous cholecystitis, 25 with acute non-gangrenous cholecystitis, and 27 without cholecystitis). The following findings were evaluated: distention, mural thickening, wall enhancement, irregular wall, wall striation, intraluminal membranes, pericholecystic inflammation, gallstones, pericholecystic fluid, enhancement of liver parenchyma, pericholecystic abscess, and gas in the wall or lumen. Sensitivity and specificity of CT for gangrenous cholecystitis and for each finding were calculated. Two reviewers in consensus measured gallbladder dimension and wall thickness. Logistic regression models were used to predict gangrenous versus non-gangrenous cholecystitis.

RESULTS

Sensitivity, specificity, and accuracy of CT for acute cholecystitis were 91.7%, 99.1%, and 94.3%, respectively, and for acute gangrenous cholecystitis were 29.3%, 96.0%, and 64.1%, respectively. Findings with the highest specificity for gangrenous cholecystitis were gas in the wall or lumen (100%), intraluminal membranes (99.5%), irregular or absent wall (97.6%), and abscess (96.6%). The difference between the mean gallbladder wall thickness and the short-axis dimension for the two groups with cholecystitis was statistically significant. In three patients with gangrenous cholecystitis, no mural enhancement was seen. Pericholecystic fluid also achieved statistical significance for the diagnosis of gangrene. Multivariate logistic regression analysis showed that the overall accuracy of CT for gangrenous cholecystitis was 86.7%.

CONCLUSION

CT findings most specific for acute gangrenous cholecystitis are gas in the wall or lumen, intraluminal membranes, irregular wall, and pericholecystic abscess. Gangrenous cholecystitis is associated with a lack of mural enhancement, pericholecystic fluid, and a greater degree of gallbladder distention and wall thickening.

Neutrophilic dermatosis of myeloproliferative disorders. Atypical forms of pyoderma gangrenosum and Sweet's syndrome associated with myeloproliferative disorders

Atypical forms of pyoderma gangrenosum (PG) and Sweet's syndrome (SS) (acute febrile neutrophilic dermatosis) have been separately reported in association with various forms of leukemia over the past decade. A case in which both atypical bullous PG and atypical SS occurred in a patient with myeloid metaplasia is presented, and the literature is reviewed concerning the association of these dermatoses with neoplasias of myeloid origin. The current case and review support the thesis that these dermatoses, when associated with myeloproliferative disorders, represent points on a continuum of noninfectious, nonmetastatic, inflammatory neutrophilic dermatoses that may occur in patients with derangements in myeloid cell proliferation.

Acute acalculous cholecystitis. An increasing entity

Acute acalculous cholecystitis was observed to increase in frequency between 1950 and 1979, an increase that was statistically significant. The greatest part of this increase occurred between 1965 and 1979. Acute acalculous cholecystitis was also found to be associated with a higher mortality rate, more than twice that of acute calculous cholecystitis. Acute acalculous cholecystitis occurred in a variety of clinical settings including bacterial sepsis, severe trauma including surgical trauma and burns, multiple transfusions, and severe debilitation. The lesion in the gallbladder consists of intense injury of blood vessels in the muscularis and serosa similar to those induced experimentally by in vivo activation of factor XII dependent pathways. Possibly because of the intensity of vascular injury, acute acalculous cholecystitis with minimal clinical manifestations may rapidly progress to gangrene with perforation. Undelayed surgical treatment, which has become more widely accepted over the past 50 years, is essential. It may have also contributed to the increased recognition of this clinical entity.

Trends in the care of the diabetic foot. Expanded role of arterial reconstruction

In recent years, our operative approach to ulceration and gangrene in the diabetic foot has changed markedly. We now investigate all such patients for ischemia, even in the presence of neuropathy and localized infection. This strategy is based on a rejection of the concept of a microvascular occlusive lesion, an improved understanding of the pattern of atherosclerotic occlusion, an emphasis on arteriographic delineation of the foot arteries, and increasing success with extreme distal arterial reconstruction, especially vein bypass grafts to the dorsalis pedis artery. From 1984 through 1990, 2883 procedures were performed at our institution on patients with diabetes mellitus. There was a statistically significant decrease in every category of amputation, which correlated precisely with the increasing rate of dorsalis pedis artery bypass. Our indications for surgery, in-hospital mortality, and the bypass-associated amputation rate did not change.

Impaired red cell deformability in peripheral vascular disease

By means of a recently developed technique, red-cell deformability was measured in 44 patients with peripheral vascular disease and in 44 age and sex matched normal control subjects. 28 patients had intermittent claudication and 16 rest pain or gangrene. The ability of the red cells to deform was significantly reduced in patients and significantly less in patients with rest pain or gangrene than in those who only had intermittent claudication. A reduction in red-cell deformability by retarding blood-flow through the microcirculation may be an important factor in states of peripheral vascular insufficiency.

Acute cholecystitis in the elderly: a surgical emergency

A retrospective review of 88 male patients older than 60 years of age with billiary tract disease showed a mortality of 6.8%. More than 40% of the patients (39 of 88) had acute cholecystitis. Medical therapy failed for almost all of the patients (38 of 39) with acute inflammatory disease and they then required an operation during their initial hospitalization. In this acute disease group, 21% had empyema of the gallbladder, 18% had gangrenous cholecystitis or free perforation of the gallbladder, and 15% had subphrenic or liver abscesses. Escherichia coli and Klebsiella were obtained from 78% of the bile cultures, and obligate anaerobes were present in 25% of them. A delay in diagnosis and operation occurred in 33% of the patients with acute disease. Factors responsible for this delay included a deceptively benign clinical presentation and the requirement for prolonged resuscitation. Since response to conservative measures is unlikely in the elderly patient with acute cholecystitis, optimal management consists of resuscitation and prompt operation for control of infection.

Ecthyma gangrenosum: report of clinical, histopathologic, and bacteriologic aspects of eight cases

The records of eight patients with ecthyma gangrenosum who were treated at the Mayo Clinic between 1970 and 1982 were reviewed. All patients had hematologic disease and had received immunosuppressive drugs. Patients with neutropenia that did not resolve by the end of a course of appropriate antibiotic treatment usually died. Solitary lesions of ecthyma gangrenosum were associated with a better prognosis than were multiple lesions. The typical skin findings of ecthyma gangrenosum usually occurred early and were often incorrectly diagnosed, resulting in time lost during which antibiotic therapy could have been instituted. For patients with ecthyma gangrenosum, a systematic procedure is important to establish the diagnosis early, so that appropriate systemic antibiotic therapy can be initiated.

The role of epinephrine in the reactions produced by the endotoxins of gram-negative bacteria. I. Hemorrhagic necrosis produced by epinephrine in the skin of endotoxin-treated rabbits

Extensive lesions of dermal hemorrhagic necrosis occurred in rabbits when epinephrine (or norepinephrine) was injected into the skin within 4 hours after an intravenous injection of endotoxin. As little as 5 microg. of intradermal epinephrine, and 1 microg. of intravenous endotoxin, were sufficient to produce lesions. Similar lesions, but smaller in size and surrounded by a zone of acute inflammation, were produced by intradermal injection of a mixture of comparable amounts of endotoxin and epinephrine. No lesions were produced by combinations of endotoxin with serotonin, pitressin, or ephedrine. Both types of epinephrine-endotoxin lesion were prevented by pretreatment with cortisone, dibenzyline, and chlorpromazine. They were not prevented by heparin or nitrogen mustard. The lesions produced by intradermal mixtures of epinephrine and endotoxin were greatly enhanced in size and severity in animals treated with nitrogen mustard. Both types of lesion were prevented in rabbits rendered "tolerant" by repeated injections of sublethal amounts of endotoxin. It is concluded that endotoxin has the property of altering the reactivity of blood vessels to epinephrine in such a way that this hormone becomes a potent necrotizing agent. The possibility that this effect may represent a basic mechanism in the various intoxicating actions of endotoxin, and certain implications of this hypothesis, are discussed.

Low-intensity laser irradiation improves skin circulation in patients with diabetic microangiopathy

OBJECTIVE

Diabetic foot problems due to angiopathy and neuropathy account for 50% of all nontraumatic amputations and constitute a significant economic burden to society. Low-intensity laser irradiation has been shown to induce wound healing in conditions of reduced microcirculation. We investigated the influence of low-intensity laser irradiation by means of infrared thermography on skin blood circulation in diabetic patients with diabetic microangiopathy.

RESEARCH DESIGN AND METHODS

Thirty consecutive patients with diabetic ulcers or gangrenes and elevated levels of glycosylated hemoglobin were randomized by blocks of two to receive either a single low-intensity laser irradiation with an energy density of 30 J/cm2 or a sham irradiation over both forefoot regions in a double-blind placebo-controlled clinical study. Skin blood circulation as indicated by temperature recordings over the forefoot region was detected by infrared thermography.

RESULTS

After a single transcutaneous low-intensity laser irradiation, a statistically significant rise in skin temperature was noted (P < 0.001 by ANOVA for repeated measurements), whereas in the sham-irradiated control group, a slight but significant drop in temperature (P < 0.001) was found. Subsequently performed contrasts for comparison of measurements before and after irradiation revealed significant temperature increases at 20 min of irradiation time (P < 0.001), at the end of the irradiation (P < 0.001), and 15 min after stopping the irradiation (P < 0.001). In the sham-irradiated feet, the drop in local skin temperature was not significant at 20 min (P = 0.1), but reached significance at the end of the sham-irradiation procedure (P < 0.001) and 15 min after the end of sham irradiation (P < 0.001).

CONCLUSIONS

The data from this first randomized double-blind placebo-controlled clinical trial demonstrate an increase in skin microcirculation due to athermic laser irradiation in patients with diabetic microangiopathy.

Superficial granulomatous pyoderma: a localized vegetative form of pyoderma gangrenosum

Twenty-five patients had superficial ulcerative and vegetative pyoderma with granulomatous histologic findings. Healing occurred without systemic corticosteroid therapy in all but three patients. All patients had clinical pyoderma gangrenosum. In five patients the lesion occurred after surgery of the skin. Histopathologic study of 40 biopsy specimens showed focal neutrophilic abscesses of the papillary dermis, often with peripheral palisading histiocytes and foreign-body giant cells. Pseudoepitheliomatous, vegetative hyperplasia and sinus tract formation were observed frequently. All patient had massive areas of plasmacytosis, and 13 had eosinophils. Granulation tissue, hemorrhage, and fibrosis were additional features in some areas. Foreign material in the lesions was considered unimportant, except in one patient with a starch granuloma. Therapy with local corticosteroids, minocycline, tetracycline, or sulfa drugs resulted in healing in 15 patients. We believe that we have identified a localized, limited form of chronic superficial pyoderma gangrenosum with verrucous and ulcerative lesions and a granulomatous histologic appearance that represents a unique pattern of this disease in some patients.

Amyand's hernia: case report and review of the literature

The authors report a case of gangrenous acute appendicitis in the sac of an inguinal hernia (Amyand's hernia). After a review of the literature, they emphasise the extreme rarity of the case reported, they underline how the clinical picture is highly similar to that of a strangulated inguinal hernia. They affirm that appendicectomy and hernioplasty may be performed at the same time, since the repair of the hernia should be performed without prosthesis implantation due to the contamination of the operating field.

Pyoderma gangrenosum: a review

Pyoderma gangrenosum is a poorly understood disease characterized by exacerbations and remissions of morphologically unique skin ulcers. It frequently is thought to be the cutaneous manifestation of an underlying systemic disease. In this review of pyoderma gangrenosum, the characteristics of the disease are described and a differential diagnosis is formulated. Associations with systemic diseases are made through a review of the literature. The pathophysiology of pyoderma gangrenosum and probable causes are considered, and special consideration is given to the immunologic mechanisms that may be operative in the disease. Finally the currently available therapeutic alternatives are reviewed.

Phlegmasia caerulea dolens and venous gangrene

Phlegmasia caerulea dolens and venous gangrene are rare conditions that tend to occur in association with malignancy. They are characterized by total or near-total occlusion of the venous drainage of the limb, including the microvascular collaterals. Associated mortality and morbidity rates are high, especially when progression to venous gangrene has occurred. Treatment options are limited; elevation and anticoagulation are recommended as first-line management. Experience with thrombolysis has been disappointing although intra-arterial administration of thrombolytic agents may improve results. Thrombectomy cannot be advocated routinely. Little advance in management, or in life and limb salvage, has been made in the past 30 years.

Purpura fulminans and symmetrical peripheral gangrene caused by Capnocytophaga canimorsus (formerly DF-2) septicemia--a complication of dog bite

We review the syndrome of Capnocytophaga canimorsus (DF-2) septicemia after exposure to dogs or cats. We describe a previously healthy patient who developed diffuse intravascular coagulation and symmetrical peripheral gangrene as a result of C. canimorsus septicemia after a dog bite. To our knowledge, this patient was the first to receive combined plasmapheresis and leukapheresis for C. canimorsus septicemia. Symmetrical peripheral gangrene is frequently associated with C. canimorsus septicemia and may lead to an early diagnosis in patients who become severely ill after a dog bite. Other complications include arthritis, meningitis, and endocarditis. These manifestations can also be found in previously healthy patients, although a prior splenectomy or other causes of impaired host defense clearly enhance the risk. Prompt treatment with penicillin G is required.