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Keith K Lau

Publications and source records attributed to Keith K Lau.

11 recordsLinked to original sources
PubMed2006

Short-term outcomes of severe lupus nephritis in a cohort of predominantly African-American children.

Renal involvement is one of the major determinants of the outcome in patients with systemic lupus erythematosus. Although African-American ethnicity has been suggested to be a poor prognostic factor in severe lupus nephritis in adult patients, information on outcomes of African-American children with this disease is still very limited. We retrospectively studied the patients diagnosed with severe lupus nephritis by renal biopsy at Le Bonheur Children's Medical Center from January 1990 to December 2003. All patients were below the age of 18 years at the time of biopsy. Clinical features assessed included age, gender, race, estimated glomerular filtration rate (GFR), presence of hypertension, gross hematuria, degree of proteinuria, complement 3 and 4 levels, serum albumin, renal histology and dose of oral prednisone. Forty-four patients were studied: 82% were African-American and 89% were female. Mean age at biopsy was 14.2+/-3 years (median 15.0 years; range 4.7 years to 17.0 years). Renal biopsies were assessed according to the WHO classification. Twenty-seven percent, 43%, and 30% were in class III, IV and V, respectively. At presentation, 55% had hypertension and 23% had a history of macroscopic hematuria. The patients had varying degrees of proteinuria, including 18% with nephrotic syndrome. Eighteen percent had moderate renal insufficiency with estimated GFRs less than 50 ml/1.73 m2 body surface area per minute. All the patients were treated with corticosteroids. Sixty-eight percent also received cyclophosphamide and 20% received either mycophenolate mofetil (MMF) or azathioprine (AZA). Two patients developed end stage renal disease and required chronic dialysis within 12 months of biopsy. At the 12-month follow-up visit, 23% of patients had complete remission and 48% had partial remission. The mean estimated GFR had increased from 96.0 ml/1.73 m2 per minute to 124 ml/1.73 m2 per minute (P=0.03). Mean serum creatinine levels decreased from 1.62 mg/dl to 0.91 mg/dl (P=0.03). Complement 3 levels increased from 54.3 mg/dl to 90.3 mg/dl (P<0.01). Mean serum albumin levels also increased from 2.8 mg/dl to 3.6 mg/dl (P<0.01) and urine protein-to-creatinine ratio decreased from 5.8 to 1.0 (P<0.01). The average prednisone dose decreased from 0.96 mg/kg per day to 0.41 mg/kg per day (P=0.64). In our center, with predominantly African-American children, patients with lupus nephritis presented similarly to those in other studies with predominantly Caucasian patients, and short-term renal outcomes were not different.

Adolescent↗
PubMed2006

Five years' experience with thymoglobulin induction in a pediatric renal transplant population.

Antibody induction therapy is used in the majority of pediatric patients undergoing renal transplantation. Our center has previously reported short-term outcomes with TMG as induction therapy. We now present our experience over the last five yr. Patients received TMG intra- and post-operatively at a dose of 1.5 mg/kg/day. The dose was decreased to 0.75 mg/kg/day or held dependent on the patient's WBC and platelet counts. Post-transplant immunosuppression also included corticosteroids, MMF, and either TAC or CSA. Patient and graft survival, number of acute rejection episodes, creatinine clearance, incidence and type of infections, and trough levels of calcineurin inhibitor drugs were monitored during the follow-up period. Thirty-four renal transplants were performed in 33 pediatric patients ranging in age from 1.7 to 17.8 yr. Seventeen rejection episodes occurred during the time of follow-up with three patients having more than one episode, but only three episodes occurred within the first year after transplantation. Three patients had graft loss in the first week after transplantation from primary non-function (1) or technical failure/thrombosis (2). Graft losses occurred in seven additional patients during the time of follow-up with the first loss occurring at 17.7 months. Among patients with functional grafts at one wk after transplant, graft survival at one and three yr was 100% and 73% respectively. There were no patient deaths. There were no cases of post-transplant lymphoproliferative disease or other malignancy. One patient had symptomatic CMV disease. TMG is safe and effective as induction therapy in pediatric renal transplant patients. Late graft loss remains a challenge in the pediatric patient population, particularly in adolescents.

Adolescent↗
PubMed2005

C1q nephropathy: features at presentation and outcome.

The study population comprised all 20 patients followed since 1990 through December 2004 at the Le Bonheur Children's Medical Center with diagnosis of C1q nephropathy (55% boys; 60% African Americans). All were aged under 18 years at biopsy (mean 11.2 years, 65% aged 11 or over); the youngest presented at age 10 months and progressed to end-stage renal disease at 14 months. None had clinical or laboratory features of systemic lupus erythematosis or membranoproliferative glomerulonephritis. Clinical features assessed at diagnosis were age, gender, blood pressure, history of macroscopic hematuria, urinary protein to creatinine ratio, serum creatinine, estimated glomerular filtration rate, renal histology, and pattern for immunofluorescent reactants. At the time of biopsy 40% had nephrotic syndrome and 30% nephrotic range proteinuria without nephrotic syndrome. Three patients with nephrotic syndrome also had chronic renal insufficiency at diagnosis. The most common histological feature was focal segmental glomerulosclerosis in 40%, but 30% had minimal change lesion. Four patients, all with nephrotic syndrome at diagnosis, progressed to end-stage renal disease. Of the 12 patients not presenting with nephrotic syndrome, none had chronic renal insufficiency at last follow-up. Kidney survival was 94% and 78% at 1 and 5 years, respectively, in all patients and 88% and 49% in those presenting with nephrotic syndrome.

Adolescent↗
PubMed2005

Glomerulonephritis.

GN in the adolescent requires prompt diagnosis. When even mild degrees of renal insufficiency are documented, immediate referral to a nephrologist is necessary to ensure that serious conditions, such as RPGN, are correctly diagnosed and aggressively managed. In an adolescent with macroscopic hematuria, the demonstration of dysmorphic RBCs, RBC casts, and proteinuria indicates that the bleeding is of glomerular origin. Physicians caring for adolescents with chronic GN should have a basic understanding of the specific disorders. They may be involved in blood pressure monitoring and should be aware of the potential side effects of the antihypertensive and immunosuppressive medications used in patients with GN.

Acute Disease↗
PubMed2005

Polyuria associated with high-dose methotrexate in two patients with acute lymphoblastic leukaemia.

Although methotrexate has an established safety profile in clinical practice, severe morbidity can still occur on rare occasions. We report two patients with leukemia treated with high dose methotrexate. Both patients developed profound polyuria that required aggressive fluid resuscitations during the treatments. Renal toxicity is a known complication of methotrexate, but polyuria associated with its use has not been reported before. Polyuria started shortly after the initiation of the medicine in both patients. The polyuria resolved as the drug level in blood became undetectable. The episodes of polyuria were transient and recurred every time when the patients received methotrexate. The clinical pictures were not compatible with classical drug induced nephrogenic diabetes insipidus. It is possible that the drug interferes with adenosine metabolism, which in turn alters the tubular ability of solute and fluid reabsorption.

Adenosine↗