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Query: UMLS:C0002895 (sickle cell disease)
 11,747 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Leg ulcers are a well recognized complication of sickle cell disease that has been attributed to venous insufficiency. We studied 16 patients with sickle cell disease and active ulcers using venous pulse volume recordings and photoplethysmography (Doppler studies). Based on hemodynamic monitoring, all 16 patients exhibited rapid refilling times, findings that imply venous insufficiency but are also compatible with high-output syndrome or arteriovenous shunting. Direct invasive venous pressure measurements of these patients demonstrated normal pressures in all of the four patients tested. A different set of four patients underwent venography, which also failed to demonstrate venous incompetence. We hypothesize that anemia results in an increase in peripheral arteriovenous shunting in the extremities and that this, together with the high-output syndrome of sickle cell disease, produces plethysmography readings that may be confused with findings observed in venous insufficiency. We conclude that measurements of vascular stasis, as recorded by plethysmography, are usually misinterpreted in sickle cell disease. Normal manometric pressure readings and normal venographic studies suggest that venous insufficiency is not a primary factor in sickle cell leg ulcer formation.
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PMID:Venous insufficiency is not the cause of leg ulcers in sickle cell disease. 206 60

We treated five adult individuals with six full-thickness chronic ulcerations in the skin caused by venous insufficiency, sickle cell anemia, or surgical wounds. Each patient received applications to the ulcerations of sheets of autologous epidermal cells grown in culture. All patients experienced relief of pain after grafting. Four of the six ulcers healed completely in 21 to 35 days, and three of the four remained healed for up to 2 years. One ulceration recurred within 2 months. Our experience suggests that cultured autologous epidermal grafts can provide continuous covering, relief from pain, and rapid healing of chronic debilitating ulcerations of the skin.
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PMID:Grafting of skin ulcers with cultured autologous epidermal cells. 395 55

Simultaneous resurfacing of extensive soft-tissue defects involving both lower extremities can be performed successfully with free hemiflaps harvested from the omentum. This avoids the need for staged operations or for separate donor sites with the concomitant morbidities, the possible need for intraoperative repositioning, and the significantly greater operative time. During the past 3 years, six omental free hemiflaps were performed in three patients for bilateral lower limb reconstruction. All patients had extensive ulcerations, averaging 207.5 cm2 in surface area. Ulcerations were secondary to either homozygous sickle cell anemia (two patients) or chronic venous insufficiency (one patient). Operative time averaged 11 hours for the bilateral procedures. Delayed skin grafting was performed in two patients. All six omental free hemiflaps were successful. Partial skin-graft loss due to infection occurred in both sickle cell anemia patients. Significant improvement in symptoms was noted in all patients. There were no donor-site complications. Free hemiflaps harvested from the omentum can provide sufficient well-vascularized tissue with large-caliber vessels for coverage of separate extensive soft-tissue defects in one operation with minimal donor-site morbidity, making this an ideal flap option when multiple sites are involved.
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PMID:Simultaneous reconstruction of extensive soft-tissue defects of both lower limbs with free hemiflaps harvested from the omentum. 904 96

The non-healing leg ulcer is examined by discussing three disease processes: peripheral vascular occlusive disease (PVOD), chronic venous insufficiency (CVI), and vasculitis. For PVOD, management decisions are based on risk factors and disease history. Comprehensive management includes the discontinuation of smoking, exercise conditioning and regulation of diabetes, hyperlipidemia, hypertension, and the appropriate application of anticoagulant/antiplatelet drugs. Methods of surgical management include bypass with autogenous or synthetic material in addition to reconstructive surgery with patch angioplasty or extra-anatomic bypass, amputation, percutaneous transluminal angioplasty/stents, thrombolytic infusion, atherectomy, intraluminal ultrasound, and angioscopy. The optimal healing environment for all ulcers prevents contamination, pain, and fluid loss. In CVI, higher venous pressure in the veins of the lower limb during exercise results in ambulatory venous hypertension and ulceration. Various theories are associated with the disease and ulceration process; the classic treatment of elevation, ambulation, and compression for venous disease remains unchallenged. Diagnosis is based on history, physical examination, invasive venography, and/or non-invasive studies. Two groups of vasculitic disorders that share varying degrees of vascular inflammation and necrosis are arteritis (lupus, erythematosus, periarteritis nodosa, dermatomyositis) and blood dyscrasias (sickle cell disease, thalassemia). Leg ulcers associated with vasculitis are due to inadequate tissue oxygenation at the local level, are typically chronic, slow to heal, and commonly recur.
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PMID:The non-healing leg ulcer: peripheral vascular disease, chronic venous insufficiency, and ischemic vasculitis. 939 80

Evaluating tetanus immune status is not yet the usual clinical practice regarding patients with chronic ulcers or myasis. However, of 858 tetanus patients at Hospital Couto Maia (Salvador, Bahia, Brazil) aged 1 year or above, 2 had pressure ulcers and 17 had chronic ulceration of the lower limbs where these skin lesions were the ports of entry for Clostridium tetani. In these 19 cases, the following predisposing factors were described: venous insufficiency (n=6), sickle cell anemia (n=2), Hansen s disease (n=1), malnutrition (n=1), diabetes mellitus (n=1), trauma (n=1) and unknown factors (n=7). In 6 other cases, in addition to the Hansen s disease patient, the port of entry for tetanus was the site of extraction of Tunga penetrans larvae. In these 25 cases, the majority of patients (68%) were over 40 years old (17/25) and all of these patients stated that they had either not followed a tetanus toxoid vaccination regimen (19/25), or had partially completed such a regimen, or did not give precise information (6/25). Among the same series studied, over half (52%) of the patients died (13/25). We conclude that tetanus prevention must be included in the treatment of chronic skin ulcer patients, vaccination coverage should be increased among older people, and strategies aimed at improving coverage for all age groups must be reviewed.
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PMID:Chronic ulcers and myasis as ports of entry for Clostridium tetani. 1198 May 94

Homozygous sickle cell anaemia (SS disease) involves a high prevalence of skin ulcerations, and background experience concerning the cutaneous microcirculatory flux and reactivity in this disease is very limited. We investigated, by laser-Doppler velocimetry, the microcirculatory cutaneous blood flow and vasoreactivity in 17 patients with SS disease but no cutaneous trophic changes, vs. the corresponding values in 18 normal matched controls. The laser-Doppler probe was placed on the foot dorsum, and recordings were made in the supine and dependent positions, and after post-ischaemic hyperaemia. The venoarteriolar reflex was calculated as the difference between the fluxes in the supine and dependent positions. In both positions, patients with SS disease exhibited clear vasodilation, with larger cutaneous fluxes than those of the controls (P=0.024 and 0.0009, respectively). The venoarteriolar reflex, expressed as a percentage of the resting supine flux, was lower in the patients (P=0.0004). These impairments of the microcirculatory fluxes, which combine a vasodilated state with abnormal vasoreactivity, resemble those observed in patients with chronic venous insufficiency and might be crucial in determining the pathogenesis of the skin ulcerations that occur in SS disease. Laser-Doppler velocimetry seems a suitable non-invasive technique for investigating such cutaneous microangiopathy.
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PMID:Cutaneous microvascular blood flow and reactivity in patients with homozygous sickle cell anaemia. 1222 89

In this brief review, we have examined some clinical conditions that result to be associated to an altered hemorheological profile and at times accompanied by skin ulcers. This skin condition may be observed in patients with the following condtions, such as primary polycythemic hyperviscosity (polycythemia, thrombocytemia) treated with hydroxyurea, primary plasma hyperviscosity (multiple myeloma, cryoglobulinemia, cryofibrinogenemia, dysfibrinogenemia, and connective tissue diseases), primary sclerocythemic hyperviscosity (hereditary spherocytosis, thalassemia, and sickle cell disease). In addition, it may be present in patients with secondary hyperviscosity conditions such as diabetes mellitus, arterial hypertension, critical limb ischemia and chronic venous insufficiency.
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PMID:Clinical conditions responsible for hyperviscosity and skin ulcers complications. 2855 Feb 39