A novel mutation of the alpha2-globin causing alpha(+)-thalassemia: Hb Plasencia [alpha125(H8)Leu--Arg (alpha2)

We describe, in a Spanish family with moderate microcytosis and hypochromia, a novel nondeletional alpha-thalassemia (thal) mutation localized on the alpha2-globin gene. DNA sequencing revealed a point mutation at codon 125 (CTG --> CGG) in the heterozygous state, that was confirmed by restriction analysis. The resulting variant, which causes a nondeletional alpha-thal, was named Hb Plasencia [alpha125(H8)Leu --> Arg (alpha2)] after the place of residence of the affected family.     

The ABO blood group genotype and factor VIII levels as independent risk factors for venous thromboembolism

Factor VIII (FVIII), von Willebrand factor (vWF) and the ABO blood groups have been associated with thrombosis. The ABO locus has functional effects on vWF and FVIII levels and is genetically correlated with FVIII, vWF and thrombosis. We carried out a case-control study to assess the role of FVIII, vWF and ABO types on thrombotic risk. We analyzed 250 patients with venous thrombosis and 250 unrelated controls. FVIII, vWF and other factors related to thrombophilia were measured, ABO groups were analyzed by genotyping. FVIII and vWF were higher in non-O individuals. Group O was more frequent in the controls (44.3% v 23.3%; difference 21.1%; 95% CI: 13.0-29.3%) and Group A in patients (59.2% v. 41.5%; difference 17.7%, 95% CI: 9.1-26.4%). Individuals carrying the A1 allele had a higher risk of thrombosis (OR 2.6; 95% CI, 1.8-3.8). The risk attributed to vWF disappeared after adjusting for the ABO group. Patients with FVIII above the 90th percentile had a high thrombotic risk (adjusted OR 3.7; 95% CI, 2.1-6.5), and a high risk of recurrence (OR 2.3; 95% CI: 1.3-4.1). In conclusion, high FVIII levels and non-O blood groups, likely those with the A1 allele, are independent risk factors for venous thromboembolism and should be considered in evaluating of thrombophilia.     

Mycobacterium chelonae tenosynovitis of the hand

OBJECTIVE: Tenosynovitis of the hand due to atypical mycobacteria is an uncommon condition. We present a case of tenosynovitis of the hand due to Mycobacterium chelonae in a patient without a recognized penetrating injury, who was treated successfully with clarithromycin and antituberculous medications and without debridement. We reviewed the available literature to summarize the experience with this infectious entity. METHODS: Case report and review of the literature (MEDLINE 1976-2003). Only cases that were sufficiently detailed were included. RESULTS: Twelve cases of upper extremity infection due to M. chelonae have been reported: hand tenosynovitis in most and arthritis in a few. These infections resulted from percutaneous inoculation or hematogenous seeding. The clinical course was indolent initially but insidiously destructive. Previously, treatment always included surgical excision of the infected tissues and antibiotic therapy. This is the first case of M. chelonae musculoskeletal infection that resolved with only antimicrobial therapy. CONCLUSIONS: Musculoskeletal infections by nontuberculous mycobacteria are clinically indistinguishable from those of tuberculosis and diagnosis is usually delayed. Prompt diagnosis of atypical mycobacteria with appropriate antimicrobial treatment may avoid the need for surgical debridement. Relevance We recommend a trial of antibiotics for M. chelonae before surgical debridement.     

The treatment of varicocele by microsurgical techniques

We performed an extensive bibliographic search, and review the alternatives for surgical treatment of varicocele, especially microsurgical techniques. The surgical techniques for varicocele have not suffered much variation over the last years, being their use generalized among urologists. The lower incidence of relapse and secondary hydrocele to lymphatic lesion make retroperitoneal techniques be used less frequently in favour of inguinal or subinguinal techniques, microsurgical or not. For better understanding of the surgical indications and development of techniques we offer some short anatomical and physiopathological comments about varicocele.     

Pseudotumor renal after partial nephrectomy with the use of surgical gelatin sponge

After renal parenchymal sparing surgery, with the use of surgical gelatin sponge, residual defects may persist on imaging studies at the sites of resection. These "pseudotumors" may lead to confusion as to whether a lesion was removed or has recurred. These lesions usually resolve within a year. We report a case of pseudotumor renal parenchymal sparing surgery in a 69 year old man, with resolution of the lesion 8 months after surgery.     

Zinc and Lead Poisoning in Wild Birds in the Tri-State Mining District (Oklahoma,Kansas, and Missouri)

The Tri-State Mining District (Oklahoma, Kansas, and Missouri) is contaminated with Pb, Cd, and Zn from mining, milling and smelting. Metals have been dispersed heterogeneously throughout the District in the form of milled mine waste (chat), as flotation tailings and from smelters as aerial deposition or slag. This study was conducted to determine if the habitat has been contaminated to the extent that the assessment populations of wild birds are exposed to toxic concentrations of metals. American robins (Turdus migratorius), northern cardinals (Cardinalis cardinalis), and waterfowl had increased Pb tissue concentrations (p < 0.05) compared with Pb tissue concentrations from reference birds, and the exposure of songbirds to Pb was comparable with that of birds observed at other sites severely contaminated with Pb. Mean activities of the Pb-sensitive enzyme delta-aminolevulinic acid dehydratase (ALAD) were decreased by >50% in red blood cells in these birds (p < 0.05). Several birds had tissue concentrations of Pb that have been associated with impaired biological functions and external signs of poisoning. Cadmium was increased in kidneys of songbirds (p < 0.05), but no proximal tubule cell necrosis associated with Cd poisoning was observed. Zinc concentrations in liver and kidney of waterfowl were significantly higher (p < 0.05) than reference values. The increased environmental concentrations of Zn associated with mining in the District accounted for the pancreatitis previously observed in five waterfowl from the District. The District is the first site at which free-flying wild birds have been found to be suffering severe effects of Zn poisoning.     

Association after linkage analysis indicates that homozygosity for the 46C-->T polymorphism in the F12 gene is a genetic risk factor for venous thrombosis

In a family-based study called GAIT (Genetic Analysis of Idiopathic Thrombophilia) that included a genome-wide scan we demonstrated that a polymorphism (46C-->T) in the F12 locus jointly influences variability of plasma (Factor XII) FXII levels and susceptibility to thrombotic disease. It then became germane to determine the prevalence of the 46C-->T polymorphism and its relative risk of thrombotic disease. We followed up evidence for genetic linkage with a case-control study, including 250 unrelated consecutive Spanish patients suffering from venous thrombotic disease and 250 Spanish subjects matched for sex and age as a controls. We measured FXII levels and genotyped the 46C-->T polymorphism, as well as a number of classical risk factors for thrombotic disease.We confirmed that individuals with different genotypes for this polymorphism showed significant differences in their FXII levels. Most importantly, the mutated T allele in the homozygous state (genotype T/T) was associated with an increased risk of thrombosis (adjusted OR of 4.82; 95% CI 1.5-15.6), suggesting that the polymorphism itself is an independent risk factor for venous thromboembolism. This study confirms that the 46C-->T polymorphism is a genetic risk factor for venous thrombosis in the Spanish population. In addition, our results confirm that a genome-wide scan coupled with a classical case-control association study is an extremely valuable approach to identify DNA variants that affect complex diseases.