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Biomedical subjects

S Y Ha

Publications and source records attributed to S Y Ha.

72 records · Page 4Linked to original sources
PubMed1993

Childhood acute lymphoblastic leukaemia presenting with relapsing hypoplastic anaemia: progression of the same abnormal clone.

A 13-year-old girl presented with two spontaneously reversible episodes of marrow hypoplasia. She subsequently developed acute lymphoblastic leukaemia (ALL) 8 months later. Southern analysis showed identical clonal immunoglobulin heavy chain gene rearrangement bands in the leukaemic cells as well as the marrow cells obtained at the two hypoplastic episodes. Hypoxanthine phosphoribosyl transferase polymorphism studies showed that the ALL blast cells, bone marrow and peripheral blood cells during the two hypoplastic episodes all exhibited clonal haematopoiesis with the same X-chromosome inactivated. This case provides strong evidence that aplastic anaemia and ALL may represent evolution of the same abnormal clone.

Adolescent↗
PubMed1993

Interstitial deletion of 9q revisited.

Interstitial deletion of the long arm of chromosome 9 (9q-) is an uncommon karyotypic abnormality in acute myeloid leukemia (AML). We report a case of acute myeloid leukemia, M6 according to the FAB criteria, in which 9q- was the sole karyotypic abnormality. From our own experience and that in the literature, interstitial 9q- seems to be associated with two specific morphologic/cytogenetic categories: AML M2 and t(8;21)(q22;q22)/trisomy 21; and as the sole karyotypic aberration in AML M1/M2(M6) with dyserythropoiesis. Examination of the published karyotypes shows that 9q13 to 9q21 is the commonest deleted segment, suggesting that this region may carry genes important in leukemogenesis.

Acute Disease↗
PubMed1992

Lung involvement in Langerhans' cell histiocytosis: prevalence, clinical features, and outcome.

In Langerhans' cell histiocytosis, the prognostic significance of pulmonary disease is controversial. The clinical and radiological features and lung function tests of Langerhans' cell histiocytosis patients presenting to a single tertiary referral center between 1981 and 1987 were reviewed. Age at diagnosis ranged from 2 weeks to 16 years (median 1.7 years) and the male-female ratio was 2.4:1. No child presented with lung involvement alone. In 18 (40%) of 45 patients with multisystem disease there was clinical and/or radiological evidence of lung pathology. Another 6 children (13%) with normal chest roentgenograms had abnormal lung function tests, suggesting subclinical ("occult") involvement. Those with overt lung disease tended to present at a younger than average age (median 0.6 years). The most common functional disturbance was reduced lung or respiratory compliance with reduced lung volumes. Patients with and without lung involvement showed a similar pattern of involvement of other organs, with skin and bone most commonly affected. Of the 45 children with multisystem disease, 38 (84%) survived 2 to 7 years after diagnosis; there was a similar proportion of deaths in children with and without lung involvement. It is concluded that lung involvement occurs in nearly half of young children with multisystem Langerhans' cell histiocytosis but does not adversely affect outcome.

Adolescent↗
PubMed1991

The acute lupus hemophagocytic syndrome.

OBJECTIVE: To characterize an unusual mode of presentation of systemic lupus erythematosus: acute and severe pancytopenia related to reactive hemophagocytosis. DESIGN: Retrospective case series. SETTING: Two general community hospitals in Hong Kong. PATIENTS: Six patients presenting with a reactive hemophagocytic syndrome, identified over a 3.5 year period, diagnosed with systemic lupus erythematosus according to the criteria of the American Rheumatism Association. RESULTS: In addition to severe pancytopenia and marrow hemophagocytosis, other characteristic features were fever, hypocomplementemia, high antinuclear antibody titer, and cutaneous and visceral vasculitis. There was no evidence of an underlying infection. The pancytopenia responded dramatically to treatment with steroids. CONCLUSION: Recognition of the acute lupus hemophagocytic syndrome and distinction from an infection-associated hemophagocytic syndrome is important because it responds well to steroid therapy. The evaluation of patients presenting with a hemophagocytic syndrome should include serologic tests for systemic lupus erythematosus.

Acute Disease↗
PubMed1991

Arteriovenous malformation of the uterus--a cause of massive operative bleeding.

Arteriovenous malformations of the uterus are extremely rare and they occur either in congenital or acquired forms. The most common clinical presentation is abnormal uterine bleeding, which may be aggravated by therapeutic curettage. Because of their rare incidence and clinical importance in management of patients, we report a case of arteriovenous malformation causing serious bleeding during a hysterectomy for uterine leiomyoma. The patient was a 47-year-old multiparous woman who had a history of chronic vaginal bleeding for one year. Numerous anomalous blood vessels draining into the right and left uterine arteries were found on the anterior wall of the uterus and parametrium.

Arteriovenous Malformations↗
PubMed1986

AIDS in a Hong Kong Chinese.

A young Hong Kong Chinese male patient with fever of unknown origin is presented. The diagnosis of acquired immunodeficiency syndrome was made only 5 months after the onset of his illness. The lack of awareness of the syndrome might account for the delay in the diagnosis. The legal attitude towards homosexuality might have an adverse effect on epidemiological studies of AIDS in Hong Kong.

Acquired Immunodeficiency Syndrome↗
PubMedDate not supplied

Reactive hemophagocytic syndrome in childhood--frequent occurrence of atypical mononuclear cells.

Reactive hemophagocytic syndrome, which is characterized by systemic proliferation of benign hemophagocytic histiocytes, usually presents as an acute febrile illness with pancytopenia and hepatosplenomegaly. The commoner diseases associated with the syndrome are infection and malignant lymphoma. In this report, eight cases of reactive hemophagocytic syndrome occurring in infants and young children are described. Unlike the disease occurring in adults, there is frequent occurrence of atypical mononuclear cells both in the peripheral blood and bone marrow. The morphological spectrum of these atypical cells is however still within that seen in infectious mononucleosis, and their reactive nature is substantiated by their spontaneous disappearance and subsequent recovery of the patients. It is important to distinguish this reactive proliferation from the neoplastic cells of 'malignant histiocytosis' or malignant lymphoma, since cytotoxic drugs are not warranted for treatment of this non-neoplastic condition.

Adolescent↗
PubMedDate not supplied

Presacral epidermoid cyst: imaging findings with histopathologic correlation.

BACKGROUND: The aim of this study was to determine the imaging characteristics of presacral epidermoid cysts and correlate the imaging findings with the histopathologic findings. METHODS: We retrospectively reviewed sonographic, computed tomographic, and magnetic resonance examinations in four consecutive patients with a pathologically proven presacral epidermoid cyst. Imaging findings of the presacral epidermoid cyst were correlated with the histopathologic findings. RESULTS: In all four patients, sonography showed a presacral mass with a heterogeneous low echogenicity, and computed tomography showed a discrete well-defined hypodense presacral mass with a thin wall. In the three patients who underwent magnetic resonance imaging, the mass showed a heterogeneous low signal intensity on the T1-weighted image and a high signal intensity with multiple small foci of low signal intensity in the nondependent portion of the mass on the T2-weighted image. These imaging findings correlated well with the pathologic results. Aggregates of keratinous material contributed to these imaging findings. CONCLUSION: In the diagnosis of the presacral epidermoid cyst, sonographic and magnetic resonance imaging findings may be helpful.

Adult↗
PubMedDate not supplied

Sibling HLA-matched cord blood transplant for beta-thalassemia: report of two cases, expression of fetal hemoglobin, and review of the literature.

PURPOSE: A program of cord blood stem cell (CBSC) transplants for patients with beta-thalassemia major was initiated in conjunction with the prenatal diagnostic service in 1994. Two patients who received HLA-matched related CBSC transplants with posttransplant fetal hemoglobin (HbF) expression are described and the literature is reviewed. PATIENTS AND METHODS: After screening 12 pregnancies, matched sibling CBSC transplants were performed for 2 girls with beta-thalassemia major when they were 3.8 and 2.2 years old, respectively. Their HbF was assayed serially. RESULTS: The nucleated cell counts/kg were 11.4 x 10(7) and 6.2 x 10(7), which engrafted on days 19 and 24, respectively. The children are now transfusion-independent at 3 years and 1.2 years posttransplant. Their HbF levels showed a rapid rise posttransplant and reached peak levels of 37.2% and 42.2% on day 83 and day 88, respectively. The HbF levels declined to 1.0% and 3.8% on day 581 and day 305, respectively. Nine other sibling CBSC transplants for thalassemias have been reported with an engraftment rate of approximately 50%. Graft rejection was related to insufficient CBSC number in one. CONCLUSIONS: HbF levels in patients with beta-thalassemia major after CBSC transplants could be influenced by many factors, including reactivation of HbF synthesis, intrinsic rate of Hb switching of CBSC, and mixed chimerism.

Female↗
PubMedDate not supplied

Lymph node metastasis and lymph vascular space invasion in microinvasive squamous cell carcinoma of the uterine cervix.

The objective of this study was to determine whether the depth of invasion was related to lymph vascular space invasion (LVSI) and lymph node metastasis and whether there was a correlation between LVSI and lymph node metastasis in stage IA cervical cancer. The medical records, including surgical notes and pathologic reports, of 202 patients with microinvasive squamous cell carcinoma of the uterine cervix were reviewed retrospectively. There was a positive correlation between the depth of invasion and the LVSI, and the incidence of lymph node metastasis was slightly higher than those reported hitherto for stage IA1 cervical cancer, especially in the depth of invasion of 1-3 mm group. However, among four patients with lymph node metastasis, only two patients had positive LVSI. There was no definite correlation between LVSI and lymph node metastasis. LVSI could not identify the patients with high risk for lymph node metastasis.

Adult↗
PubMedDate not supplied

What is the difference between squamous cell carcinoma and adenocarcinoma of the cervix? A matched case-control study.

The objective of this study was to investigate the efficacy of treatment strategies in patients with adenocarcinoma (AC) of the cervix and compare it with those with squamous cell carcinoma (SCC) of the cervix. Women with FIGO (1994) stage IB1 AC, especially pathologic tumor size of 2-4 cm, treated with class III hysterectomy, were compared with those with SCC treated with comparable strategy in a case-controlled study. Eighty patients (20 cases, 60 controls) were analyzed. Lymphvascular space invasion (P = 0.01) and lymph node metastasis (P = 0.07) were more frequent in patients with SCC than in those with AC. However, there was no significant difference in depth of stromal invasion (P = 0.51) and invasion of the parametrium (P = 0.44) between two groups. And there was also no statistically significant difference in disease-free survival (P = 0.86) and overall survival (P = 0.89) between two groups. Primary radical surgery followed by adjuvant therapy, same as for SCC, would be acceptable for AC with pathologic tumor size of 2-4 cm. Although it was difficult to determine whether AC recurred more systemically, more effective treatment strategies than those currently available for AC should be considered to reduce the systemic recurrence.

Adenocarcinoma↗
PubMedDate not supplied

Listeria septicemia complicating bone marrow transplantation for Diamond-Blackfan syndrome.

Infection with Listeria monocytogenes is uncommon in patients receiving cytotoxic chemotherapy, and is even rarer among recipients of bone marrow transplantation. Hemosiderosis, either idiopathic or caused by transfusion, appears to be another risk factor. We report a 3-year-old Chinese girl with transfusion-dependent Diamond-Blackfan syndrome who had L. monocytogenes septicemia when she received an allogeneic bone marrow transplantation. She was treated successfully with intravenous ampicillin. Our case adds to the clinical evidence that patients with iron overload are susceptible to listeriosis, particularly when they are immunocompromised and do not receive iron-chelation treatment.

Bacteremia↗
PubMedDate not supplied

Plesiomonas shigelloides septicemia: case report and literature review.

A 13-year-old girl with Plesiomonas shigelloides septicemia is reported. The infection occurred while she was receiving an allogeneic bone marrow transplantation for acute promyelocytic leukemia. Treatment with ciprofloxacin was successful. Twenty-one cases of Plesiomonas septicemia have been reported in the literature. Immunocompromised hosts, especially neonates, are commonly affected. The case mortality rate is high, with 13 of the reported patients dying of the infection. Successful treatment relies on the early identification of the organism and implementation of effective antibiotics.

Adolescent↗
PubMedDate not supplied

Multidisciplinary management of osteosarcoma: experience in Hong Kong.

All pediatric osteosarcomas treated in our hospital between 1985 and 1995 were reviewed. There were 26 patients, 15 males and 11 females, aged 20 or less at diagnosis. All had limb primaries. Nineteen patients had localized disease and seven presented with metastases. Intensive multiagent chemotherapy was given both pre- and postoperatively. Most patients were treated with the Rosen T10 regimen or its modifications. Only one patient had limb salvage surgery; all others had amputation. With a median follow-up of 74 months, the 5-year disease-free survival among patients with localized disease was 65.2%. Being female and having a high 6-hour postinfusion methotrexate level with a median level greater than 700 mumol/L were good prognostic factors. Three of the seven patients with metastatic disease were alive at 21, 26, and 140 months after diagnosis. All of them had lung secondaries. Survival rates achieved in our center were comparable to those reported in literature. However, our amputation rate was high and further development in expertise for limb salvage treatment is a goal.

Adolescent↗
PubMedDate not supplied

Prevention of beta-thalassemia major by antenatal screening in Hong Kong.

The thalassemias are common in Hong Kong. One of the severe forms, beta-thalassemia major, has been preventable locally by antenatal screening since 1983. Yet new patients are still being diagnosed. In this retrospective study, 34 children with severe beta-thalassemia syndromes were diagnosed in two major public hospitals between 1990 and 1996. They included one pair of identical twins and two pairs of siblings. Twenty-seven (79%) had homozygous beta-thalassemia and seven (21%) had beta E thalassemia. All but four (12%) were transfusion dependent. Fifty-five (89%) parents had been evaluated for their thalassemia status. Forty-eight had beta-thalassemia traits and seven were hemoglobin E carriers. The reasons for the birth of these children with severe beta-thalassemia syndromes were (1) late or no antenatal visit (n = 8, 24.2%), including three cross-border deliveries in which the pregnant mothers came from mainland China to Hong Kong for confinement, (2) lack of maternal screening (n = 13, 39.4%), (3) lack of paternal screening (n = 7, 21.2%), (4) parental refusal (n = 3, 9.1%), and (5) unknown (n = 2, 6.1%). These findings suggest that several factors undermine the effectiveness of antenatal screening for prevention of thalassemias. Many medical practitioners and the general public are still not aware of the screening procedures. The migration of population from mainland China to Hong Kong may result in the birth of many more children with beta-thalassemia major.

Female↗