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J V Harmon

Publications and source records attributed to J V Harmon.

8 recordsLinked to original sources
PubMed2005

Hemolysis during percutaneous mechanical thrombectomy can mimic a hemolytic transfusion reaction.

BACKGROUND: Interventional radiologists have developed percutaneous mechanical thrombectomy (PMT) devices to remove intravascular thrombi. Hemolysis, secondary to thrombus destruction from these devices, has been described in radiology journals, but similar reports appear to be lacking in the transfusion medicine literature. Two cases of hemolysis after PMT are described that involved the transfusion service, one of which was reported as a hemolytic transfusion reaction. CASE REPORTS: The first patient received 4 units of red cells (RBCs) during a thrombectomy and subsequent placement of a transjugular intrahepatic portosystemic shunt. The patient developed hemoglobinuria, and it was reported to the blood bank as a possible hemolytic transfusion reaction. After RBC mismatch and bacterial contamination were excluded, the hemolysis was attributed to thrombectomy-related mechanical hemolysis. In the second case, a hemolyzed sample was sent to the blood bank for a type and cross-match. Upon requesting that the sample be redrawn, it was learned that the sample was obtained after PMT. CONCLUSION: Patients who have undergone PMT can have clinical and laboratory findings suggestive of hemolytic transfusion reactions. Although interventional radiologists are familiar with these side effects, the blood bank profession needs to be aware that these procedures cause nonimmune hemolysis and must consider this possibility when evaluating transfusion reactions in these patients.

Aged↗
PubMed2001

Experimental short-term immunosuppression after bowel transplantation and donor-specific bone marrow infusion.

HYPOTHESIS: We previously showed in a large animal pig model that unmodified donor-specific bone marrow infusion (DSBMI) did not facilitate total bowel engraftment; in contrast, it increased the risks of rejection, infection, and graft-vs-host disease (GVHD) posttransplant. We hypothesize that continuous immunosuppression, in combination with DSBMI, might contribute to-or even trigger-these unwarranted immune responses by both host and graft; therefore, discontinuing immunosuppression might decrease these risks and prolong survival. METHODS: Six groups of outbred, mixed lymphocyte culture-reactive pigs underwent a total (small and large) bowel transplant: group 1, nonimmunosuppressed control pigs (n = 5); group 2, nonimmunosuppressed DSBMI pigs (n = 6); group 3, tacrolimus (indefinite) pigs (n = 7); group 4, tacrolimus (indefinite) plus DSBMI pigs (n = 7); group 5, tacrolimus (10 days only) pigs (n = 5); and group 6, tacrolimus (10 days only) plus DSBMI pigs (n = 6). RESULTS: The combination of short-term immunosuppression and DSBMI (group 6) significantly prolonged survival, compared with short-term immunosuppression only (group 5) or DSBMI only (group 2). Short-term immunosuppression and DSBMI (group 6) did not prolong overall survival, compared with indefinite immunosuppression with (group 4) or without (group 3) DSBMI: survival rates at 7, 14, and 28 days posttransplant were 100%, 100%, and 67% in group 6; 100%, 100%, and 71% in group 3; and 100%, 67%, and 47% in group 4 (P =.14). Short-term immunosuppression and DSBMI (group 6) increased the incidence of rejection, infection, and GVHD, compared with indefinite immunosuppression without (but not with) DSBMI. CONCLUSIONS: Short-term immunosuppression and DSBMI did not prolong survival and did not reduce the incidence of death from rejection, infection, or GVHD, compared with indefinite immunosuppression without DSBMI. But short-term immunosuppression and DSBMI resulted in a lower incidence of death from infection and GVHD, compared with indefinite immunosuppression and DSBMI. When immunosuppression was discontinued 10 days posttransplant, the effect of DSBMI was insufficient to avert death from rejection. CLINICAL RELEVANCE: The clinical results of bowel transplantation trail those of other solid organ transplants. It reduced the rates of infection and GVHD. Our study shows that systemically infused donor-specific bone marrow with short-term or indefinite immunosuppression does not improve outcome after bowel transplantation. It seems necessary to modify the time, dosing, routing, and/or composition of donor-specific bone marrow before it can be successfully used in clinical bowel transplantation.

Animals↗
PubMed1998

Donor-specific portal blood transfusion in intestinal transplantation: a prospective, preclinical large animal study.

BACKGROUND: Unlike in kidney and heart transplantation, the role of pretransplant donor-specific blood transfusion (DST) has not been studied prospectively in a large animal model of bowel transplantation. We investigated the impact of portal versus systemic DST on overall survival, rejection, graft-versus-host disease (GVHD), and infection after total (small and large) bowel transplantation in pigs. METHODS: Mixed lymphocyte culture-reactive, outbred pigs underwent total enterectomy and orthotopic total bowel transplantation with portal vein graft drainage. One unit of donor blood was transfused via the portal or systemic circulation (according to a randomization protocol) before graft implantation was begun. We studied six groups, all of which underwent at least a total bowel transplant: group 1 (n=5) comprised nonimmunosuppressed control pigs with portal DST; group 2 (n=6), nonimmunosuppressed control pigs with systemic DST; group 3 (n=5), cyclosporine (CsA)-treated pigs with portal DST; group 4 (n=5), CsA-treated pigs with systemic DST; group 5 (n=5), tacrolimus-treated pigs with portal DST; and group 6 (n=5), tacrolimus-treated pigs with systemic DST. All immunosuppressed pigs received prednisone (2 mg/kg/day) and either CsA (to maintain levels between 250 and 350 ng/ml) or tacrolimus (to maintain levels between 10 and 30 ng/ml). Stomal biopsies and autopsies were obtained to study the incidence of rejection, GVHD, and infection. RESULTS: Portal DST and tacrolimus-based immunosuppression resulted in the highest survival rates. At 7, 14, and 28 days after transplantation, survival rates in group 5 were 100%, 100%, and 80%; in group 6, 100%, 60%, and 40%; and in group 3, 100%, 0%, and 0%, respectively. Only the combination of portal DST and tacrolimus prevented the occurrence of, and death from, rejection. Death from rejection at 7, 14, and 28 days in group 5 was 0%, 0%, and 0%; in group 6, 0%, 33%, and 67%; and in group 3, 0%, 100%, and 100%, respectively. Of note, if immunosuppression was used, the groups with portal (versus systemic) DST had a higher risk of death from infection but a lower risk of death from GVHD. Simultaneous immunologic events were noted more frequently in groups with systemic (versus portal) DST. Long-term survival was noted only in groups with tacrolimus-based immunosuppression and was more common for those with portal (versus systemic) DST. CONCLUSIONS: Portal DST at the time of total bowel transplantation and posttransplant immunosuppression with tacrolimus prevent rejection and significantly increase graft survival. The combination of portal antigen presentation and tacrolimus needs to be studied in clinical bowel transplantation.

Animals↗
PubMed1995

Symmetrical terminal transverse limb defects: report of a twenty-week fetus.

A 20-week gestation hydropic Thai fetus is reported who had symmetrical absence of each hand and forefoot with persistence of digit-like nubbins on each limb. The histologic studies showed there was calcified acellular material in the digit-like nubbins, consistent with infarcted blood vessels, and cartilaginous structures that represented possibly the distal metacarpal articulating surface. The red blood cell indices of both parents were consistent with their being heterozygous for a hemoglobinopathy, such as alpha-thalassemia, which is common in Thais. The infarcted blood vessels could be the result of thrombosis of the digital arteries in the fetus due to a hemoglobinopathy such as hemoglobin Bart's, just as rabbit fetuses homozygous for brachydactyly have transverse terminal digit amputations following digital vessel occlusions due to macrocytic anemia. This was the only child with symmetrical absence of the hands and feet identified among 123,489 liveborn and stillborn infants surveyed for major malformations.

Female↗
PubMed1995

Red cell alloimmunization after a bone allograft.

BACKGROUND: Alloimmunization to blood group antigens other than ABH after bone allografting is uncommon. To date, examples of alloimmunization to blood group antigens other than ABH have been limited to the Rh system. CASE REPORT: A 20-year-old woman received an allogeneic bone graft following resection of an osteosarcoma. The patient had received no blood components and denied any pregnancies. Alloimmunization was detected and alloantibodies were identified by standard serologic techniques. Fourteen months after the bone graft, anti-Fya and anti-Jkb were identified in her serum. CONCLUSION: Alloimmunization to blood group antigens other than ABO and Rh may follow bone allografting.

Adolescent↗
PubMed1995

Leukocytoclastic vasculitis following staphylococcal protein A column immunoadsorption therapy. Two cases and a review of the literature.

BACKGROUND: Protein A immunoadsorption is a novel therapy for the treatment of diseases mediated by pathogenic autoantibodies. This procedure consists of circulating patients' plasma through a column containing staphylococcal protein A, which binds to the Fc portion of IgG, enabling removal of IgG. Presently, protein A immunoadsorption is used in the treatment of idiopathic thrombocytopenic purpura, but may be more widely used as an immunomodulator in human immunodeficiency virus infection and metastatic carcinoma. OBSERVATIONS: We present two histologically documented cases of leukocytoclastic vasculitis in the setting of protein A immunoadsorption. This potentially severe adverse effect is probably more common than the literature reflects and should be recognized by physicians who are treating patients with protein A column pheresis. CONCLUSIONS: The pathogenesis of protein A therapy-associated leukocytoclastic vasculitis remains unclear. Further study of vasculitis in the setting of protein A column pheresis may lead to modifications of this therapy, resulting in fewer adverse effects. Protein A-associated leukocytoclastic vasculitis may serve as a useful model of the relation of immune complexes and vasculitis.

Aged↗
PubMed1987

Venous valves in subclavian and internal jugular veins. Frequency, position, and structure in 100 autopsy cases.

Valves in the subclavian and internal jugular veins were studied in 100 autopsy cases (52 men and 48 women; range, 18 to 91 years old; mean, 67 years). In 87 cases, valves were present in all 4 veins, and in 13 cases, valves anatomically were absent from 16 veins, 9 of which were the left internal jugular vein. The average distance from the valve to the junction with the innominate vein was 1.7 cm for the subclavian vein and 0.3 cm for the internal jugular vein. Cuspid height averaged 0.9 cm. Valves were bicuspid in 347 (90%) and unicuspid in 39 (10%); unicuspid valves were more common in the internal jugular vein than in the subclavian vein. Catheter-induced trauma was observed in 4 cases and implied in 4 more. These findings may have important implications concerning the failure, in some cases, of closed-chest cardiac resuscitation to maintain forward blood flow at adequate pressure.

Adolescent↗