Mexican consensus on lysosomal acid lipase deficiency diagnosis. / Consenso mexicano sobre el diagnóstico de la deficiencia de lipasa ácida lisosomal.

INTRODUCTION: Lysosomal acid lipase deficiency (LAL-D) causes progressive cholesteryl ester and triglyceride accumulation in the lysosomes of hepatocytes and monocyte-macrophage system cells, resulting in a systemic disease with various manifestations that may go unnoticed. It is indispensable to recognize the deficiency, which can present in patients at any age, so that specific treatment can be given. The aim of the present review was to offer a guide for physicians in understanding the fundamental diagnostic aspects of LAL-D, to successfully aid in its identification. METHODS: The review was designed by a group of Mexican experts and is presented as an orienting algorithm for the pediatrician, internist, gastroenterologist, endocrinologist, geneticist, pathologist, radiologist, and other specialists that could come across this disease in their patients. An up-to-date review of the literature in relation to the clinical manifestations of LAL-D and its diagnosis was performed. The statements were formulated based on said review and were then voted upon. The structured quantitative method employed for reaching consensus was the nominal group technique. RESULTS: A practical algorithm of the diagnostic process in LAL-D patients was proposed, based on clinical and laboratory data indicative of the disease and in accordance with the consensus established for each recommendation. CONCLUSION: The algorithm provides a sequence of clinical actions from different studies for optimizing the diagnostic process of patients suspected of having LAL-D.

A Scheduled Program of Molecular Screening for Epstein-Barr Virus Decreases the Incidence of Post-transplantation Lymphoproliferative Disease in Pediatric Liver Transplantation.

This is a cohort, retrospective, comparative study of all liver transplant recipients from a single center, from May 1998 to July 2015. Patients were divided into two groups according to the type of Epstein-Barr viral load monitoring. For group I (1998-2007), polymerase chain reaction (PCR) was not available or it was only qualitative with limited access. For group II (2008-2015), we used periodically scheduled quantitative PCR in plasma and leukocytes, with aggressive tapering of immunosuppression as soon as viral replication was detected. Ninety-eight recipients were included, 41 (41.8%) were Epstein-Barr virus (EBV) - seronegative before liver transplantation (LT). EBV replication was confirmed in 74 patients (75.5%), being more frequent in seronegative (87.8%) than seropositive patients (66.6%). Eight recipients (8.1%) developed post-transplantation lymphoproliferative disorder (PTLD) on average at 14.3 months post-LT, seven of eight were <3 years at LT, four of eight were D+/R- for EBV, and all had post-LT EBV replication confirmed by PCR. PTLD was classified as lymphoma (n = 4), polymorphic polyclonal (n = 3), and lymphoid hyperplasia (n = 1). Five patients died, and three cleared PTLD after immunosuppression tapering or interruption. There were no significant differences in the etiology, age at LT (5.6 vs. 7.3 years, P = .069), patients <4 years (53.2% vs. 35.3%, P = .103), or EBV seronegative recipients (44.7% vs. 37.3%, P = .54); however, the incidence of PTLD decreased from 14.9% to 1.9% (P = .026), and graft rejection from 51.1% to 29.4% (P = .039). One- and 5-year patient survival rates were 94.7% and 85%, respectively, with no differences between groups. This strategy dramatically decreased the incidence of PTLD (14.9% vs. 1.9%), without increasing the incidence of rejection; therefore, we recommend that it should be used in the follow-up of all pediatric LT recipients.

Analysis of the genotypic diversity of strains of Helicobacter pylori isolated from pediatric patients in Mexico.

Genotypic differences in Helicobacter pylori play an important role in infection. We characterized the diversity of the cagA, cagE, babA2, and vacA genes in H. pylori strains isolated from pediatric patients and the relationship between these genes and clinical disease. Additionally, we employed the Neighbor-net algorithm to predict the behavior of the genotypes of the strains isolated from patients. Of 93 patients analyzed, 32 were positive for infection. A total of 160 H. pylori strains (five isolates per positive patient) were analyzed. A total of 91% and 83% of strains possessed the cagA and cagE genes, respectively. For the vacA gene, 84% of strains possessed the s1 allele, 15% the s2 allele, 81% the m1 allele and 13.8% the m2 allele. The babA2 gene was present in 79% of strains. Infection with H. pylori strains with the vacA (s1m1) genotype was associated with risk of esophagitis and gastritis (p=0.0001). The combination of cagA and vacA (s1m1) was significantly associated with abdominal pain (p=0.002); however, EPIYA type was not significantly associated with abdominal pain. A total of 16 different genotypes were identified; the most common genotype was vacAs1m1cagA+cagE+babA2+ (47.5%). A total of 84% of pediatric patients were infected by at least two and up to five different genotypes. The network recovered two genotype groups (A: strains with vacAs1 and B: strains with vacAs2). The presence of multiple paths in the network suggests that reticulate events, such as recombination or reinfection, have contributed to the observed genotypic diversity.

Experience of a successful pediatric liver transplant program in Mexico.

Orthotopic liver transplantation (OLT) has been very difficult to develop in Mexico and for many years its occurrence was anecdotal. This report presents the results of a pediatric liver transplant program, analyzing the variables that affect outcomes. Between June 1998 and March 2004, 35 OLT were performed in 34 recipients including 80% cadaveric whole-organ grafts and 20% segmental grafts, with 11% from cadaveric and 9% from living donors. Most of the recipients were infants or toddlers weighing less than 15 kg. There was only 1 case of arterial thrombosis (2.8%); the graft was saved with a Kasai procedure. Biliary complications were present in 22% of cases, all resolved with reoperations. Posttransplant cytomegalovirus infection or reactivation (28%), acute rejection (25%), or posttransplant lymphoproliferative disorders (5.7%) were not a cause of graft or patient loss. Overall, 1- and 5-year patient survival rates are 77.1% and 74.2%, respectively; however, when the 1998-2000 cohort was compared with the 2001-2004 cohort, there was a significant difference in survival (P = .004). The 1-year patient survival for the later group is 91.6%. We performed the first successful living donor liver transplantation and the first simultaneous liver-kidney transplantation in a child in our country. Our results demonstrate that pediatric liver transplantation is a feasible undertaking in Mexico, with survival rates comparable to those of foreign centers.

The right atrioventricular valvular apparatus in the chick heart.

The purpose of this study was to describe the detailed anatomy and histology of the right atrioventricular valve apparatus in the chicken. Newborn and adult chicken hearts were studied by anatomic description, light and scanning electron microscopy, and histologic (Masson's trichrome stain) and histochemical (Sirius Red stain) techniques. Our findings indicate the presence of an incomplete fibrous annulus, a great mural leaflet, and multiple microleaflets in the right atrioventricular apparatus of the chicken heart. The great mural leaflet, essentially muscular in structure, extended from the anterior and posterior juxtaseptal commissures and was subdivided into an anterior and a posterolateral region by the attachment of the anterolateral papillary muscle. The posterolateral region presented an intermediate cleft, subdividing this region into an anterior and a posterior portion. Multiple microleaflets, which adhered to the upper right side of the ventricular septum adjacent to the right atrioventricular orifice, inserted directly into the ventricular septum via short chordae tendineae, without papillary muscles. The microleaflets were composed of smooth subendocardial connective tissue, with varying amounts of type I, II and III collagen. In addition, we observed a central fibrous body, leading to fibrous continuity between the mitral and aortic valves and the mitral and right atrioventricular valves. An atrioventricular septum was also present.(ABSTRACT TRUNCATED AT 250 WORDS)

[Central nervous system pathology in children with AIDS]. / Patología del sistema nervioso central en niños con síndrome de inmunodeficiencia adquirida.

The neuropathological manifestations of AIDS in children vary widely and includes, among others: cerebral atrophy, basal ganglia calcification, corticospinal tract demyelinization, and HIV encephalomyelitis with multinucleated cells. The purpose of this work is to inform the postmortem CNS findings in 14 pediatric AIDS patients which were studied from January 1986 to February 1992, at the Hospital Infantil de México Federico Gómez. Basal ganglia vascular calcification, HIV multinucleated cells, and corticospinal tract demyelinization, were significantly less frequent (P < 0.01) in our patients than those informed in the literature. Opportunistic CNS infections found in our patients were produced by microorganisms commonly described in adults. We think that these differences may be explained because the majority of our patients acquired the infection trough blood transfusion at an age in which the CNS is fully developed. The pattern of HIV transmission in our country has been changing recently with an increase in the number of perinatal cases. We also think that in the near future we will observe a change in the neuropathological findings of our pediatric AIDS population.

[Nephrotic syndrome associated with AIDS in children]. / Síndrome nefrótico asociado al síndrome de inmunodeficiencia adquirida en niños.

Several renal and renal-related disturbances have been described in patients with AIDS (acquired immune deficiency syndrome), in adults and children as well. These are mainly electrolyte and acid-base imbalance, acute renal failure and nephrotic syndrome. The latter is usually steroid non-responder. The renal histopathological lesions described more commonly are minimal change, mesangial hyperplasia and focal segmental glomerulosclerosis. Herein, we describe a 5 year-old with AIDS, that developed nephrotic syndrome, characterized by edema, ascites, hypoalbuminemia and massive proteinuria. A percutaneous renal biopsy showed mesangial proliferation. She did not respond to a 6 week treatment with prednisone. She died with sepsis after several viral and bacterial infections.

[Oral manifestations in HIV positive children]. / Manifestaciones orales en niños positivos al virus de la inmunodeficiencia humana.

Oral manifestations of HIV infection in children include oral candidiasis, herpetic stomatitis, oral hairy leukoplakia, parotid gland swelling, and other bacterial, viral and mycotic infections. The frequency and natural history of those disorders are not fully defined. The purpose of this work is to inform the oral findings in 57 HIV infected children studied at the Hospital Infantil de Mexico. All 57 patients presented nonspecific gingivitis; however it was not feasible to associate it with the HIV infection; in 28 oral candidiasis was observed, and in 3 cases herpetic stomatitis was documented. Oral candidiasis was found regardless the patient's sex, age, clinical stage, treatment, and mode of transmission of the HIV infection. It has been considered that oral candidiasis is a good marker of immunodeficiency; however, in our patients this correlation was not observed. Also, other HIV-associated oral manifestations were not observed in these cases. The severity and rapid clinical course presented by our patients, may explain both, the lack of correlation between candidiasis and immunodeficiency as well as the absence of other lesions.

[Coronary arteriopathy associated with cardiomyopathy in an adolescent with AIDS]. / Arteriopatía coronaria asociada a cardiomiopatía en un adolescente con síndrome de inmunodeficiencia adquirida.

The purpose of this paper is to inform the case of a 15 years old male patient who died as a consequence of acquired immunodeficiency syndrome (AIDS) complications. The postmortem examination showed a coronary lesion which, to the best of our knowledge, has not been previously described. This vasculopathy was restricted to the coronary arteries; myocardial changes similar to those described in AIDS-associated dilated cardiomyopathy were also present. The coronariopathy was indistinguishable from that described in the blood vessels of the brain in patients with AIDS-related cerebral arteriopathy. We also reviewed the autopsy material from another 14 children who died of AIDS, an in none of them exhibited similar changes in the coronary arteries. In addition we present the clinical findings and some theoretical considerations regarding the pathogenesis of the lesions.

[Fever of unknown origin. Presentation of 180 pediatric cases]. / Fiebre de origen obscuro. Presentación de 180 casos pediátricos.

Fever of unknown origin (FUO) is a frequent disorder in pediatric age. FUO is defined as the presence of fever over 38.4 centigrades in a patient for more than three weeks in which the etiology remains undetermined. From 30.736 consecutive admittances into our hospital, 180 patients with FUO were detected, and studied in a systematized way and according to a predetermined protocol. FUO was commonly found in children under six years of age. Our patients presented fever from three weeks to six and a half years of evolution; however, in the vast majority of the cases (n = 115) fever had a three weeks course. Several symptoms and physical manifestations other than fever were observed in our patients but they were widely variable and nonspecific. Infectious diseases were the commonest etiological factor encountered; among them, thyroid fever, and urinary tract infections were the most frequent infectious disorder found; in four children fever was associated to ampicillin administration; in 19 patients, fever was no demonstrated. A large number of laboratory investigations were done in the diagnosis of neoplastic diseases. We think that the study of a patient with FUO requires of a systematized approach.

[The Pelger-Huët anomaly. A clinical and ultrastructural study of a family from northeastern Mexico]. / Anomalía de Pelger-Huët. Estudio clínico y ultraestructural en una familia del noroeste de México.

The Pelger-Huet anomaly is a benign disorder which affects the morphology of the granulocytes and is namely inherited as an autosomic dominant trait. The frequency of this anomaly varies from country to country and in México this constitutes the sixth family reported. This is a case of a 21-month-old boy whose anomaly was detected during the study of his ferropenic anemia with which he arrived at the hospital. During the study of his nine family members, the anomaly was found to have also been present in his father. An electron microscopy study of the subject, his father's and a normal control's neutrophils was conducted. The patient's and his father's leucocyte granules were found to be normal but decreased in number. This work includes some discussion on inherited traits, their presentation, morphology, differential diagnosis and emphasizes the importance in recognizing this anomaly and the promotion of genetic counselling.

[Congenital and neonatal varicella. A report on 9 cases]. / Varicela congénita y neonatal. Presentación de nueve casos.

Varicella infection in the first month of life is rare. Neonates may be infected through the placenta or in the perinatal period. In Mexico, the experience with neonatal varicella infection is limited; on the other hand this disease may be misdiagnosed in the neonate. The purpose of this work is to inform nine patients which presented varicella in the neonatal period; in six cases the disease was observed after the 10th but before the 30th day of life; in the remaining cases, the disease was present before the 10th day. Only one patient was premature. Five patients developed varicella in the hospital; in three cases, the mother presented the disease nine, eight, and one day prior delivery; one patient was exposed to varicella in his home. Four patients died but only in one case the death was attributed to varicella.

[Chiari malformation]. / Malformación de Chiari.

The Chiari malformation (CHM) is a congenital disease of unknown etiology. It is presumed that a defective closure of the neural tube produces at least one of its three types. It has also been related to traumatic delivery. Type II is closely associated to the myelomeningocele. The clinical picture is determined by the chronic compression of the cervical cord by the cerebellar tonsils. Low cranial nerve palsy and muscular hypotonia are some of its predominant features. Syringomyelia complicates type I. CAT scan and NMR are the preferred radiological studies for diagnosing MCH. Treatment is surgical. Posterior fossa decompression and cervical laminectomy are sufficient if the ventricular shunt is patent. If treatment is installed before permanent structural damage is present, up to 88% of the patients have significant remission of the symptoms.

[Bone disorders in children with chronic renal insufficiency exposed to high ingestion of aluminum]. / Alteraciones óseas en niños con insuficiencia renal crónica expuestos a ingestión elevada de aluminio.

Bone disorders in 28 children with chronic renal failure exposed to aluminum intoxication were studied. All of the children were in the dialysis program. Aluminum blood levels were higher than normal in all of the children and without any correlation to the magnitude of hypocalcemia or with the increase of the parathormone, which were found in different amounts in all of the children. All of the children had various degrees of skeletal retardation and only one had pathological fractures. The bone biopsy showed hypocellular marrow, decreased osteoclastic activity in the majority of the cases same as trabecular mineralization, although the amount of osteoid was lacking in the trabeculae in the majority of the cases. The deposit of aluminum was detected in a great number of them. It is concluded that osteodystrophy recognizes a number of factors as may be hypocalcemia due to a decrease in the production of 1,25-cholecalciferol, an increase in the parathyroid hormone and the deposit of aluminum, coming mainly from water, in the trabeculae which interfere with the incorporation of calcium in the formation of new bone.

Histological differences between rootlets sectioned during selective posterior rhizotomy by two surgical techniques.

During selective posterior rhizotomy, for the treatment of spasticity in infantile cerebral palsy, the rootlets to be divided are chosen by the type of electromyographic response elicited by intraoperative electrical stimulation. Two different surgical techniques were used for exposing the lumbar roots. The first approach was to expose the conus medullaris through a T 12-L 1 laminectomy, while the other approach to the dorsal roots was distally in the cauda equina through a L 2-L 3 to S1 laminectomy. Although the clinical results obtained with either of them are not very different, there is anatomical evidence that suggests that the histological structure of the divided rootlets may be different in the two techniques. We designed our study to determine of a significant difference in the number of large myelinated fibers was found between rootlets divided close to the conus medullaris and those divided distally in the cauda equina. Two groups of five children with spasticity secondary to cerebral palsy where randomly designed to be operated upon by one of the techniques. The divided rootlets were processed with standard histological techniques and the large myelinated fibers were counted on enlarged (40 x) photomicrograph of the rootlet. A significantly (p less than 0.001) larger number of large myelinated axons was found in the rootlets dissected and divided close to the conus medullaris.