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Biomedical subjects

C Mayaud

Publications and source records attributed to C Mayaud.

At least 19 recordsLinked to original sources
PubMed2000

Loss of imprinted genes and paternal SUR1 mutations lead to focal form of congenital hyperinsulinism.

Persistent hyperinsulinaemic hypoglycaemia of infancy (PHHI) is a heterogeneous disorder characterized by profound hypoglycaemia due to inappropriate hypersecretion of insulin. An important diagnostic goal is to distinguish patients with a focal hyperplasia of islet cells of the pancreas (FoPHHI) from those with a diffuse abnormality of islets (DiPHHI), because the management differs significantly. The intriguing similarity between islet cell hyperplasia and tumourigenesis prompted us to investigate whether the imprinted genes in the 11p15 region are involved. Results showed that diffuse forms are caused by constitutional homozygous or compound heterozygous mutations of the SUR1 gene. In contrast, focal forms are caused by loss of the maternally inherited 11p15 region, resulting in both loss of the maternally expressed tumour suppressor genes accounting for hyperplasia and somatic reduction to hemizygosity or homozygosity of the paternally inherited SUR1, limited to the lesion. Thus, this somatic disorder, which leads both to beta-cell proliferation and to hyperinsulinism, can be considered the somatic equivalent, restricted to a microscopic focal lesion, of constitutional uniparental disomy associated with unmasking of a heterozygous parental mutation.

Adenosine Triphosphate↗
PubMed2000

[Yellow nail syndrome. Three cases].

Yellow nail syndrome is an uncommon diagnosis established on the basis of clinical presentation with slow-growing yellow discolored nails, lymphedema, and pulmonary manifestations. We report 3 new cases with their pulmonary component.

Adult↗
PubMed1999

[Conclusion: what is the choice of antibiotics in adult respiratory tract infections?].

TREATMENT OF SINUSITIS: For both acute rhinosinusitis in patients with no past history where S. pneumoniae and H. influenzae are the main causal agents, or recurrent sinusitis in a chronic background where anaerobic bacteria are increasingly implicated, pristinamycin is one of the rare compounds which can be expected to be effective and is a treatment of choice for an empirical strategy. LOWER RESPIRATORY TRACT INFECTIONS: Besides high-risk subjects with non-microbiologically proven bronchial infection, where enterobacteriaceae could involve a pristinamycin is a useful alternative to the conventional strategy (i.e.: amoxicillin, macrolides and cotrimoxazole) in the treatment of LRT infection.

Acute Disease↗
PubMed1999

[Trismus and tetanus vaccine].

BACKGROUND: Tetanus immunization, mandatory in France before the age of 18 months, is usually well tolerated. Fever and local reaction at the site of injection are the most common side effects. We report a case of trismus associated with tetanus immunization. CASE REPORT: A 12-year-old boy was hospitalized for a trimus which occurred 22 h after a booster dose of tetanus polio vaccine. The spasm of masticator muscles was so severe that the patient had difficulties in elocution and feeding. A moderate fever and a hypertonia of the lower limbs were associated. The trismus resolved itself within about 5 min after diazepam intravenous infusion. After examination of the buccal cavity, a local cause was discarded. The outcome was favorable and the clinical status of the boy was still normal six months later. DISCUSSION: Although no similar cases have been published, 13 other comparable adverse events associated with four vaccines containing tetanus toxoid were reported to the manufacturer within a period of 12 years. During the same period, more than 66 millions doses of vaccines containing tetanus toxoid were distributed. Trisms appeared to be more likely reported in adults after booster doses. Onset of the symptoms was between a few hours to 15 days. Outcome was always favorable. CONCLUSION: Although trimus associated to tetanus toxoid immunization is rare and remains unexplained, physicians should be aware of this adverse event.

Adult↗
PubMed1999

Lymphoma of pulmonary mucosa-associated lymphoid tissue: CT scan findings and pathological correlations.

The aim of this study was to describe the lesions of pulmonary mucosa-associated lymphoid tissue (MALT) lymphoma observed by means of computed tomography (CT) and to determine the value of CT in the management of this disease. Sixty six CT scans were performed in 13 consecutive cases of histologically proven pulmonary MALT lymphoma at the time of diagnosis (n=13) or periodically (n=53). They were reviewed separately with chest radiographs by consensus between two observers. Pulmonary abnormalities were described and compared to histopathological findings on surgical specimens from seven patients. At the time of diagnosis, elementary lesions observed by means of CT consisted of nodular areas of attenuation (12 of 13), linear areas of attenuation (eight of 13) and consolidations (six of 13). All these lesions were centred on airways that appeared dilated in seven cases and were more often bilateral and multiple on CT than on the chest radiographs. CT abnormalities correlated with gross pathological appearance and were related to a lymphomatous infiltration with a peribronchovascular distribution. Pathological examination also confirmed the presence of dilated airways within lymphomatous lesions and showed that the bronchial wall was respected. During follow-up, in patients on chemotherapy, response, relapse or progression were easily identified by means of plain radiography. In the initial evaluation, computed tomography contributed to the choice of therapeutic strategy, avoiding unnecessary surgical resection in one-third of patients. By contrast, it is unclear whether computed tomography is useful for post-treatment follow-up of mucosa-associated lymphoid tissue.

Adult↗
PubMed1999

Pulmonary malignancies in the immunocompromised patient.

Clinicians should be familiar with immunodeficiency-related malignancies, as their incidence is expected to increase further with the rise in the number and survival of immunocompromised patients. The most common malignancies affecting the lungs in those patients are Kaposi's sarcoma, non-Hodgkin's lymphoma and, to a far less extent, Hodgkin's disease and bronchogenic carcinoma. However, their relative frequency depends on the types of immune deficiency, including those due to congenital disorders, AIDS and drug treatments. This review will summarize epidemiological data on the frequency of immmunodeficiency-related malignancies, recent advances on their pathogenesis and current approaches to their diagnosis and treatment in the various immunosuppressed groups.

Acquired Immunodeficiency Syndrome↗
PubMed1999

Sarcoid-like pulmonary disorder in human immunodeficiency virus-infected patients receiving antiretroviral therapy.

We report two cases of HIV-infected patients who presented with diffuse interstitial micronodular lesions on chest X-ray after institution of protease inhibitor-containing highly active antiretroviral therapy (HAART). Granulomatous pulmonary disorder mimicking sarcoidosis was diagnosed on histopathological studies revealing noncaseating granuloma and bronchoalveolar lavage analysis showing an intense CD4(+) lymphocyte alveolitis. Causative agents such as infectious organisms and environmental compounds were excluded. The relationship between sarcoid-like reaction and immune reconstitution under HAART is discussed.

Anti-HIV Agents↗
PubMed1999

AIDS-related Pneumocystis carinii pneumonia in the era of adjunctive steroids: implication of BAL neutrophilia.

Factors predictive of mortality in patients with AIDS and Pneumocystis carinii pneumonia (PCP) were identified before the introduction of adjunctive steroids, but they have not been reevaluated since. Because PCP still occurs in AIDS, remaining fatal in some cases, we conducted a multivariate analysis of factors predicting mortality in patients with HIV-positive PCP managed from 1990 to 1995, i.e., after the consensus conference on the use of adjunctive steroids. The predictive value of clinical, laboratory, and bronchoalveolar lavage (BAL) data at admission and during the course of PCP was studied retrospectively using multivariate methods, in 144 patients with AIDS. Overall mortality was 21.5%. The univariate analysis identified seven factors predictive of 90-d mortality: Pa(O(2)) on room air < 60 mm Hg, lactate dehydrogenase > 1,000 IU, albuminemia < 30 g/L, BAL neutrophilia > 10%, nosocomial infection, pneumothorax, and a need for mechanical ventilation. Four of these factors were independently associated with 90-d mortality in the multivariate analysis; among them, two were evaluable at admission, namely, Pa(O(2)) < 60 mm Hg on room air and BAL neutrophilia > 10%, and two during hospitalization, namely, the development of pneumothorax and a need for mechanical ventilation. Moreover, BAL neutrophilia was correlated to occurrence of pneumothorax and a need for mechanical ventilation. In the era of adjunctive steroid use, AIDS-related PCP remains fairly common. Two independent factors evaluable at admission, Pa(O(2)) on room air and BAL neutrophilia, are predictive of death.

AIDS-Related Opportunistic Infections↗
PubMed1999

Cardiac cause of hypoxaemia in a kyphoscoliotic patient.

This report presents the case of a 73 yr-old female in whom kyphoscoliosis, osteoporotic vertebra compression fractures and sternal injury resulted in severe respiratory failure and hypoxaemia. Pulmonary function testing showed moderate restrictive pattern and rare mismatches were found on lung ventilation/perfusion scanning. Transoesophageal echocardiography with contrast studies showed abnormal anatomic mediastinal interactions which led to right-to-left interatrial shunt, through patent foremen ovale. First-intention treatment, because of orthopaedic and respiratory surgical restraints, was to close the shunt using transcatheter devices. Follow-up after 6 months demonstrated that these interauricular umbrella devices corrected arterial hypoxaemia. True right-to-left interatrial shunts can be found in kyphoscoliotic patients, as a result of thoracic deformation, and can be safely treated with percutaneous trancatheter closure.

Aged↗
PubMed1999

[Role of thoracic radiography in the management of community-acquired pneumonia].

In patients presenting with a lower respiratory tract infection, it is generally recommended to order a chest X-ray in two circumstances: when the clinical signs suggest the diagnosis of pneumonia or in case of rather atypical symptoms suggesting a potential risk of complications. Indeed, the presence of one or more recent opacities, and more specifically, homogeneous alveolar infiltration(s) remains the gold standard criterion for the diagnosis of pneumonia. One must not however let this rule overshadow certain limitations of the chest X-ray reported in the literature: 1. the misdiagnosis of certain cases of pneumonia or bronchopneumonia seen early; 2. the extent of the infiltration gives only a very relative assessment of severity; 3. the characteristics of the infiltration are only relatively specific for etiological diagnosis. In patients with community acquired pneumonia diagnosed on the basis of clinical signs and radiographic findings, systematically performed series of follow-up X-rays have shown that the initial extension of the infiltration and the rate of its resolution contribute quite variably to the diagnosis of complications. The best indication for ordering a follow-up X-ray before 6 weeks remains an unfavorable clinical course.

Acute Disease↗
PubMed1999

Respiratory high dependency care units (RHDCU) in France.

The concept of intermediary intensive care units appeared in France with the progress of respiratory intensive care in the 1970s and an increment of the percentage of patients who were surviving an acute respiratory episode. It then became necessary to provide them with an optimal transition between the medical intensive care unit (ICU) and the home, thus explaining the emerging need for units of post-intensive care. At the present time, French health regulations recognize medical and surgical ICUs with a specific budget for equipment and nurses, and the specialized ICU which exists through a means share with the medical units (pulmonology, cardiology, etc.) inside which they are located. New regulations should make official the separation between medical and surgical intensive care units, intermediate (specialized) intensive care units and wards of reinforced follow-up, in a general perspective of improvement of the health network between the patient, home, and the different sectors of hospitalization (acute/chronic, public and private).

France↗
PubMed1998

AIDS-related primary pulmonary lymphoma.

We describe 12 cases of AIDS-related primary pulmonary lymphoma occurring between 1986 and 1996 in a large French cohort of HIV-infected patients. Diagnostic criteria were: (1) histologically proven lymphomatous pulmonary involvement; (2) absence of mediastinal and/or hilar adenopathy on chest radiography; (3) absence of extrathoracic lymphoma extension. All patients were severely immunodeficient at the time of diagnosis. All but one patient presented with B and/or nonspecific respiratory symptoms. Chest radiography showed one or more marginated nodule(s) or large mass. CT scan showed a cavitary lesion in five patients. No lymph node enlargement or specific pleural effusion was detected. Transthoracic needle biopsies were performed in 10 patients and avoided open-lung biopsy for the diagnosis of lymphoma in five patients. All but one of the primary pulmonary lymphoma were high-grade B-cell non-Hodgkin's lymphomas. Using antilatent membrane protein-1 antibodies and an Epstein-Barr-Virus-encoded RNA transcript-specific probe, latent EBV infection of tumor cells was demonstrated in every case. All but one of the patients received chemotherapy. The median survival time was 4 mo, and no patient was still alive at the cut-off date for this analysis. Progessive pulmonary lymphoma was the main cause of death, but infections were also frequent.

AIDS-Related Opportunistic Infections↗
PubMed1998

Neutrophil alveolitis in bronchioloalveolar carcinoma: induction by tumor-derived interleukin-8 and relation to clinical outcome.

Tumor infiltrate, predominantly constituted by lymphocytes, may represent an important prognostic factor in bronchioloalveolar carcinoma (BAC), in addition to tumor extension and histological type. In the present study, we determined the presence, the origin, and the prognostic importance of neutrophils that also participate in leukocyte infiltrates of BAC. Neutrophil alveolitis was determined immunohistochemically in both lung biopsies and bronchoalveolar lavage (BAL) fluid samples from 29 patients with histologically proved BAC. The local expression of interleukin (IL)-8 was determined by immunohistochemical and immunoenzymatic techniques. Neutrophil counts were analyzed in relation to the clinical outcome of patients by the Kaplan-Meier method and Cox's univariate and stepwise multivariate models. Lymphocytes and neutrophils dominated the inflammatory cell population in the lower respiratory tract of patients with BAC. Neutrophils were located mainly in the alveolar lumen and seldom in alveolar wall whereas lymphocytes were exclusively present in alveolar wall. A relationship was observed between the number of neutrophils and the level of IL-8 in BAL fluid suggesting the involvement of that chemokine in neutrophil recruitment. The tumor cells were the predominant cells that appeared to express IL-8 by immunolocalization. The presence of increased numbers of neutrophils was significantly associated with a poorer outcome in patients with BAC (P = 0.02). In a multivariate analysis, the neutrophil percentage in BAL fluid was an independent predictor of clinical outcome. The risk of death was increased substantially (rate ratio, 5.2; 95% confidence interval, 1.1 to 24.7) among patients with BAL neutrophil percentage of > or = 39% (median of the distribution) as compared with the others. In BAC, neutrophils accumulate in the alveolar lumen. Elaboration of IL-8 by tumor cells may be responsible for this event, which is associated with a significantly higher risk of death.

Adenocarcinoma, Bronchiolo-Alveolar↗