Latitudinal prevalence gradient of multiple sclerosis in Latin America.

BACKGROUND: Multiple sclerosis (MS) has a unique geographical distribution that reflects both genetic and environmental factors. Many studies have shown a positive correlation between MS frequency and latitude across both large and small geographical regions. However, scarce data have been published on the epidemiology of MS in Latin America and no study has evaluated latitudinal variation. OBJECTIVE: To evaluate the effect of latitude on MS prevalence in Latin America. METHODS: We conducted a systematic review of MS prevalence during January 2011. Prevalence rates were collected from eligible publications. The effect of latitude on prevalence was analyzed using linear regression. RESULTS: A total of ten studies were eligible for analysis, corresponding to six countries, spanning from Panama to Argentina. The crude prevalence of MS ranged from 0.75 to 21.5 per 100,000. We found a strong and significant association between prevalence and latitude (r(2) 0.8; p < 0.001) and determined an increase in prevalence of 0.33 per 100,000 per degree latitude. CONCLUSION: Our findings suggest a latitudinal prevalence gradient of MS in Latin American countries between Panama and Argentina.

Sirolimus-based immunosuppression in kidney transplantation for type 2 diabetic nephropathy.

INTRODUCTION: Kidney transplantation is the best replacement therapy of type 2 diabetic patients and recently similar graft and patient survival between diabetic and nondiabetic recipients has been reported. However, standard immunosuppressive protocols are lacking. We present our experience with sirolimus-based immunosuppression in a population of 24 type 2 diabetic patients who underwent a kidney transplantation. PATIENTS AND METHODS: From January 2001 to December 2006, 396 kidney transplantations were performed. Twenty-four patients had type 2 diabetes mellitus as a cause of end-stage renal disease. They were randomized in two groups: thirteen patients (group A) received an immunosuppressive treatment with sirolimus, low-dose tacrolimus and steroids, while 11 patients (group B) received sirolimus, mycophenolate mofetil and steroids. RESULTS: Clinical characteristics were similar between the two groups. A slightly better kidney functionality was observed in group B patients. There were neither acute rejection episodes nor severe infectious complications in both groups. One patient in each group underwent a foot amputation. Graft and patient survival was 100% for both groups at a median follow-up of 29 months. CONCLUSIONS: Sirolimus-based immunosuppression is safe and efficacious in type 2 diabetic patients who underwent a kidney transplantation, allowing a better glucose metabolism control.

Infective complications in renal allograft recipients: epidemiology and outcome.

INTRODUCTION: Successful renal transplantation strictly depends on good control of rejection and better prevention and treatment of infections, which remain serious threats. METHODS: This retrospective, observational study of 245 renal allograft recipients who underwent transplantation between January 2002 and December 2005 included a 21+/-10 months follow-up. RESULTS: A total of 110 (44.9%) patients developed an infective process during the posttransplantation period, namely, 232 infective processes. Eighty patients developed at least 1 episode of urinary tract infection (UTI) 11 patients (4%) had a wound infection, and 30 patients (12%) had pneumonia. We diagnosed 35 cases of bacteremia (35%), whereas cytomegalovirus (CMV) infection was demonstrated in 40 patients (16%). CONCLUSIONS: Immunosuppressive therapy, necessary to avoid acute and chronic rejection, exposes patients to a higher rate of infectious complications. The immunosuppressive protocols led to a relatively low incidence of infectious complications, mainly of little clinical significance. The highest incidence was evident by the sixth month after transplantation, when the immunosuppressive regimen exercised its most depressive effects on patient immune systems.

Monolateral dual kidney transplantation from marginal donors.

BACKGROUND: Dual kidney transplantation (DKT) offers a safe way to face the organ shortage with good short-term and medium-term renal function. However, its application is limited by the longer operating time and the risk of surgical complication. This study reviews our results with DKT performed with an ipsilateral technique in terms of graft loss, graft and patient survival rates, and surgical complications. PATIENTS AND METHODS: From January 2002 to March 2006, 23 patients underwent DKT through a monolateral Gibson incision with placement of both kidneys. RESULTS: One primary nonfunction occurred (4%). Delayed graft function was observed in 3 DKT (13.3%). Acute rejection rate was 4.3% (1 patient). All patients are alive at a mean follow-up of 28 months. One-year and 2-year graft survival rates were 100% and 96%, respectively. Mean serum creatinine level at 1-year posttransplantation was 1.3 mg/dL (range, 0.8-2.1 mg/dL). One DKG recipient lost 1 graft, retaining the second normal functioning graft due to ureteral necrosis. The mean hospital stay after transplantation was 15 days (range, 12-34 days). CONCLUSIONS: Monolateral placement in DKT offers the advantage of a single incision, minimizing the surgical risk. Tailored immunosuppression and careful selection of potential recipients, by excluding those with severe cardiopulmonary pathologies, could significantly improve both patient and graft survival in this group of patients.

Caspofungin in the treatment of azole-refractory esophageal candidiasis in kidney transplant recipients.

BACKGROUND: Infection is a common cause of morbidity and mortality in kidney transplant recipients. The incidence of esophageal and urogenital candidiasis in kidney and kidney-pancreas transplant recipients has not been well documented. Azoles are safe, effective agents to treat esophageal candidiasis. However, resistance to azoles is now becoming common. This study reports the use of caspofungin for the treatment of azole-resistant esophageal and urogenital candidiasis in kidney transplant recipients. PATIENTS AND METHODS: The incidence of esophageal and urogenital candidiasis was evaluated among 140 kidney transplantations and four combined kidney-pancreas transplants performed over a 2-year period. RESULTS: Twenty-two patients (15.7%) presented with esophageal candidiasis, while seven patients (5%) showed urogenital candidiasis. Thirteen patients with esophageal candidiasis (59%) and four patients (57%) with urogenital candidiasis did not improve after a week of azole treatment. A regimen of caspofungin was started in these patients, who tolerated the treatment. Urogenital candidiasis recurred in two patients 2 and 3 months after the treatment. One patient with esophageal candidiasis did not improve with caspofungin and was switched to amphotericin B therapy. There were no other recurrences of candidiasis among patients treated with caspofungin for a median follow-up of 8 months. CONCLUSIONS: Renal transplant patients remain at high risk for fungal infections. Although the number of patients was limited, the results of this study indicated that caspofungin is an effective, well-tolerated alternative for difficult-to-treat, azole-resistant candida infections in kidney and pancreas transplant recipients. The high costs of the drug limit the use of caspofungin as first-line antifungal therapy, reserving its use to recipients who had undergone unsuccessful azole therapy.

Use of hepatitis B core antibody-positive donor kidneys in hepatitis B surface antibody-positive and -negative recipients.

INTRODUCTION: The rate of hepatitis B virus transmission via organs from with isolated hepatitis B virus core antibody-positive (HBcAb+) donors in kidney transplant recipients seems very low. PATIENTS AND METHODS: Over 4 years, we performed 36 transplants from Ig HBcAb+, hepatitis B surface antigen (HBsAg)-negative donors into recipients with a history of prior hepatitis B virus (HBV) infection or reported vaccination (28 patients) and in recipients who were not immunized and received a pretransplant prophylaxis with hepatitis B immunoglobulins. We examined the HBV-related outcomes in these 36 patients in comparison with 40 recipients of allografts from HBcAb- donors. RESULTS: No patient receiving an allograft from an HBcAb+ donor developed clinical HBV infection or HBSAg positivity. The rate of seroconversion was 14.2% in immunized patients, 12.5% in nonimmunized patients, and 0% in the control group. The 17.8% of immunized patients developed elevated transaminases after transplant, in comparison with 25% and 10% in the nonimmunized patients and the control group, respectively. Graft and patient survival was 93% and 93% for immunized patients, 100% and 100% for nonimmunized patients, and 98% and 95% for the control group, respectively. CONCLUSION: The use of anti-HBc antibody-positive kidneys was associated with no risk of transmission of HBV infection, without affecting graft and patient survival, and could be considered a safe way to expand the donor pool. Our preliminary results suggest that such kidneys could be safely transplanted even in not immunized patients who underwent a prophylaxis with hepatitis B immunoglobulins.

Clinical characteristics of patients in Peru with human T cell lymphotropic virus type 1-associated tropical spastic paraparesis.

BACKGROUND: Human T cell lymphotropic virus type 1 (HTLV-1) is associated with tropical spastic paraparesis (TSP). Peru is an area of endemicity for HTLV-1. METHODS: All patients with suspected cases of TSP referred to our institute (Institute of Tropical Medicine Alexander von Humboldt, Lima, Peru) from 1989 through 2002 were interviewed and tested for HTLV-1. All patients with positive results were evaluated by an expert physician. Disease progression was defined as "rapid" if the time between TSP onset and inability to walk unaided was <2 years. RESULTS: Among 165 patients enrolled, the symptoms and signs most frequently found were spasticity (in 97.5% of patients), hyperreflexia (95.4%), lower limb paresthesia (90.2%), pyramidal signs (82.6%), urinary complaints (82.0%), and lumbar pain (79.0%). Rapid progression was present in 21.5% of patients; mean age at TSP onset was higher among these patients than among slow progressors (P<.001). Severe spasticity, diminished vibratory sensation, and tremor were found more frequently among rapid progressors, compared with slow progressors. CONCLUSIONS: HTLV-1--associated TSP is frequently diagnosed in areas of HTLV-1-endemicity. A subgroup of patients experiences rapid disease progression.

Renal transplantation with limit donors: to what should the good results obtained be attributed?

BACKGROUND: With the aim of offsetting the reduction in donors of kidneys for transplantation, we extended the acceptance criteria, considering donors over 60 years old. METHODS: The results obtained in 84 transplants carried out with this type of donor (group A) was compared with those of a control group of 125 transplants carried out with kidneys from donors under 60 years old (group B). The protocol for selection of donors was appropriate creatinine clearance, minimum proteinuria, and normal renal scan. The histological study was not included because it was not considered appropriate to assess the extent of the possible glomerulosclerosis, as this has a focal, segmented distribution. There were no significant differences between the recipients except for age (57.8 years old in group A vs. 39.2 years in group B). RESULTS: After the transplantation, there were significant differences in the duration of hospitalization (26.8 days vs. 21.8 days, P<0.009), annual plasma creatinemia (177, 225, 233, 235, and 205 micromol/L vs. 136, 150, 121, 111, and 133 micromol/L, P<0.0002/0.0004), graft survival (87%, 85%, 81%, 81%, and 81% vs. 89%, 88%, 86%, 86%, and 85%, P<0.03), and patient survival (92%, 89%, 85%, 85%, and 85% vs. 99%, 99%, 97%, 96%, and 95%, P<0.0004). Death of the patient was the only significantly more frequent cause of graft loss among group A patients (7 vs. 1 death, P<0.004). No kidney was "never working" and none were lost because of chronic rejection. CONCLUSIONS: It was concluded that elderly donors should be considered as suitable for transplantation irrespective of their chronological age, provided that they fulfill the acceptance criteria. The quality of life achieved was comparable in both groups. Despite the lower renal function in group A, this remained constant during the follow-up period.

Living kidney transplantation: a starting experience.

INTRODUCTION: We present our initial experience with living kidney transplantation. PATIENTS AND METHODS: From January 2001 to December 2002, we performed 27 living kidney transplants using immunosuppression with induction basiliximab, cyclosporine (n = 10 patients), or tacrolimus (n = 17), mycophenolate mofetil, and steroids. RESULTS: Nineteen (70.3%) donors were women and 8 (29.7%) were men of mean age 50.6 years. Four donors were over 65 years of age at the time of living donation. Donor morbidity was 5.5%: namely, one wound infection and one asymptomatic acute pancreatitis. There were no differences between the preoperative and the postoperative mean serum creatinines and systolic blood pressure values. All living donors are in good health with a mean serum creatinine of 0.80 mg/dL at a mean follow-up of 15.2 months. Nineteen (70.3%) recipients were men and 8 (29.7%) were women of mean age 36 years. Acute rejection occurred in 6 (22.2%) recipients. It was more common among spousal donors and among cyclosporine-treated recipients. Patient and graft survivals at a mean follow-up of 15.2 months was 100%. CONCLUSIONS: Our early results showed that accurate selection and preoperative management of potential living donors lead to excellent results in kidney transplantation. The health of the living donors was not impaired by the donation. The rate of early postoperative complications was low. Living donor kidney transplantation, in our geographical area with a low-rate of cadaveric donor transplants, is an alternative to expand the donor pool, which offers better results in term of patient and graft survival.

Kidney transplantation from marginal donors.

AIM: The increasing demand for transplantation and the shortage of available organs limit the success of organ transplant programs. The use of marginal donors to expand the donor pool is receiving increased attention. We reviewed a 28-month experience of kidney transplants from marginal donors to assess the impact on patient and graft survival. PATIENTS AND METHODS: From January 2001 to May 2003, 78 kidney transplants were performed, including 50 grafts from cadaver donors and 28 from living donors with 3 patients receiving a double kidney transplant. The patients were divided into 4 groups: 31 patients received a kidney from an ideal cadaver donor (group 1a); 19 patients received a graft from a marginal cadaver donor (group 1b); 19 patients received an ideal living related kidney (group 2a); and 9 patients received a marginal living kidney graft (group 2b). RESULTS: Twenty-eight grafts from marginal donors were transplanted with an average follow-up of 16 months (range, 1-28 months). The graft survival rates for groups 1a, 1b, 2a, and 2b were 93%, 79%, 100%, and 100% and patient survival rates were 96%, 89%, 100%, and 100%, respectively. CONCLUSION: Despite the observation that use of marginal donors has been associated with a worse outcome compared with ideal donors, we of such grafts resulted in improved quality of life and survival expectancy compared with maintenance dialysis. The marginal kidney donors represent a feasible way to improve the donor pool.

Early de novo malignancies after kidney transplantation.

INTRODUCTION: Immunosuppressed renal transplant patients display a higher incidence of carcinoma than the general population. The chronic use of immunosuppressive therapy to prevent acute rejection increases the long-term risk of cancer. We reviewed our experience to identify factors affecting the development of de novo neoplasms. PATIENTS AND METHODS: Between January 2000 and May 2003, 135 renal and three combined kidney-pancreas transplantations were performed. RESULTS: Sixteen (11.6%) cancers were diagnosed in nine renal transplant recipients (6.5%). Tumors presented at a mean time of 14 months. Three patients displayed in malignancies; three, Kaposi's sarcoma; one, papillary microcarcinoma of the thyroid; one, bladder carcinoma; and one, breast carcinoma. CONCLUSION: Although de novo malignancies occur more frequently many years after kidney transplantation, our experience demonstrates that they can occur early during the posttransplant follow-up. Skin malignancies showed the best prognosis, probably because of early detection and treatment. Patients with Kaposi's sarcoma benefit from reduction or cessation of immunosuppression, but this entails a higher risk of graft loss. Solid organ de novo malignancies are often more aggressive than those in normal population; the life expectancy of these recipients is low.

[Non tumor intracranial expansive processes: clinico-topographical correlation]. / Procesos expansivos intracraneanos no tumorales. Correlato clínico-tomográfico.

Presentation of clinical-tomographic correlation in 111 cases of non tumoral intracranial expansive processes seen between 1984-1988 in the Hospital Cayetano Heredia (Lima, Peru). Emphasis is given fundamentally to: (1) the importance of establishing the organicity of partial and late epilepsy; (2) the high incidence rate of inflammatory infectious processes with CNS compromise in underdeveloping countries; (3) the necessity of making public the importance of two parasitic diseases in the differential diagnosis of non tumoral intracranial expansive processes: free living amebiasis, and toxoplasmosis (especially in association with AIDS).

[Central pontine myelinolysis and pregnancy: a case report and review of literature]. / Mielinólisis central pontina y embarazo: presentación de un caso y revisión de la literatura.

INTRODUCTION: The 'rapid' correction of hyponatremia, itself a dangerous condition, is dangerous to the patient involved. There is an association between the 'rapid' correction of plasma sodium and the osmotic demyelination syndrome, characterized by the loss of myelin in the pontine neurons, and in extra-pontine sites such as the internal capsule, basal ganglia, cerebellum and cerebrum. Although cases of hyponatremia during pregnancy have been described, it has rarely been possible to demonstrate the condition, by imaging techniques or autopsy, showing demyelination lesions of the cerebrum. We report the case of a pregnant patient who developed this complication and had an interesting response to levodopa. CLINICAL CASE: A 27 year old woman had a history of progressive generalized muscle weakness for the previous six days. She had recently been discharged after receiving treatment for hyperemesis gravidarum. Imaging studies showed pontine and extrapontine myelinolysis. She was treated with levodopa which improved her extrapyramidal symptoms. CONCLUSIONS: Hyponatremia is the most commonly observed electrolyte disorder in the hospital population. The classical symptoms of myelinolysis are spastic quadriparesia and pseudobulbar paralysis, which reflect damage to corticospinal and corticobular paths. Serious symptomatic hyponatremia is a medical emergency which should be managed by specially trained personnel, since the treatment is as dangerous as the condition itself. More investigations are necessary to identify the precise risk factors and the mechanism by which an increase in sodium causes damage to myelin.

Evaluation of thyroid disease in kidney transplantation candidates: management and follow-up.

INTRODUCTION: Diagnosis of thyroid disease is fundamental in the evaluation of patients awaiting kidney transplantation. We analyzed the incidence of thyroid disease in patients with end-stage renal disease (ESRD) and evaluated its evolution before and after kidney transplantation. PATIENTS AND METHODS: Between January 2000 and May 2008, we evaluated 323 candidates for kidney transplantation. In all patients, serum concentrations of free triiodothyronine, free thyroxine, and thyroid-stimulating hormone were determined and a ultrasonography of the neck was performed. Patients with thyroid cancer were considered eligible for kidney transplantation after at least 2 years since treatment. RESULTS: One-hundred-four patients with ESRD (44%) had functional or morphologic changes in the thyroid gland. Forty-one patients (17.4%) underwent fine-needle aspiration cytology; 3 demonstrated showed papillary carcinoma; 3, follicular adenomas; 8, uncertain cytologic lesions; and 27, a nodular goiter. Seventeen patients underwent surgery. Six of 11 patients with thyroid cancer underwent transplantation: two patients underwent laterocervical lymph node dissection because of local recurrence within 2 years after successful transplantation; the other 4 patients are alive with a functioning graft. Of the 184 transplant recipients, 10 underwent surgery to treat thyroid disease: 8 with multinodular goiter, 1 with micropapillary carcinoma, and 1 with follicular adenoma. All 10 patients are alive with a well-functioning graft and no signs of disease recurrence. CONCLUSIONS: Thyroid diseases are common in patients with ESRD. Early diagnosis and treatment significantly decreased morbidity and mortality in patients awaiting transplantation.

Migraine, polycythemia and chronic mountain sickness.

In the epidemiological study among 379 adult men with permanent residence at 4300 meters (14,200 feet), we found 32.2% with migraine (mostly migraine with aura), 15.2% with tension-type headache (episodic more than chronic), and 7.2% with other headaches. The frequency of migraine increased with age from 30.1% in the 20-29 year age group to 36.8% in the 50-59 year group. Episodic tension-type headaches also showed this trend. We found an age-specific increase in the frequency of high hemoglobin (Hb > 213 milligrams), low oxygen saturation (O2 saturation < 81.5%) and high chronic mountain sickness scores. Male migraineurs and those with more than two headaches per month had the highest hemoglobin levels and chronic mountain sickness scores when compared with high altitude men without headaches.