Clinical standards for the diagnosis and management of asthma in low- and middle-income countries

BACKGROUND: The aim of these clinical standards is to aid the diagnosis and management of asthma in low-resource settings in low- and middle-income countries (LMICs).METHODS: A panel of 52 experts in the field of asthma in LMICs participated in a two-stage Delphi process to establish and reach a consensus on the clinical standards.RESULTS: Eighteen clinical standards were defined: Standard 1, Every individual with symptoms and signs compatible with asthma should undergo a clinical assessment; Standard 2, In individuals (>6 years) with a clinical assessment supportive of a diagnosis of asthma, a hand-held spirometry measurement should be used to confirm variable expiratory airflow limitation by demonstrating an acute response to a bronchodilator; Standard 3, Pre- and post-bronchodilator spirometry should be performed in individuals (>6 years) to support diagnosis before treatment is commenced if there is diagnostic uncertainty; Standard 4, Individuals with an acute exacerbation of asthma and clinical signs of hypoxaemia or increased work of breathing should be given supplementary oxygen to maintain saturation at 94-98%; Standard 5, Inhaled short-acting beta-2 agonists (SABAs) should be used as an emergency reliever in individuals with asthma via an appropriate spacer device for metered-dose inhalers; Standard 6, Short-course oral corticosteroids should be administered in appropriate doses to individuals having moderate to severe acute asthma exacerbations (minimum 3-5 days); Standard 7, Individuals having a severe asthma exacerbation should receive emergency care, including oxygen therapy, systemic corticosteroids, inhaled bronchodilators (e.g., salbutamol with or without ipratropium bromide) and a single dose of intravenous magnesium sulphate should be considered; Standard 8, All individuals with asthma should receive education about asthma and a personalised action plan; Standard 9, Inhaled medications (excluding dry-powder devices) should be administered via an appropriate spacer device in both adults and children. Children aged 0-3 years will require the spacer to be coupled to a face mask; Standard 10, Children aged <5 years with asthma should receive a SABA as-needed at step 1 and an inhaled corticosteroid (ICS) to cover periods of wheezing due to respiratory viral infections, and SABA as-needed and daily ICS from step 2 upwards; Standard 11, Children aged 6-11 years with asthma should receive an ICS taken whenever an inhaled SABA is used; Standard 12, All adolescents aged 12-18 years and adults with asthma should receive a combination inhaler (ICS and rapid onset of action long-acting beta-agonist [LABA] such as budesonide-formoterol), where available, to be used either as-needed (for mild asthma) or as both maintenance and reliever therapy, for moderate to severe asthma; Standard 13, Inhaled SABA alone for the management of patients aged >12 years is not recommended as it is associated with increased risk of morbidity and mortality. It should only be used where there is no access to ICS.The following standards (14-18) are for settings where there is no access to inhaled medicines. Standard 14, Patients without access to corticosteroids should be provided with a single short course of emergency oral prednisolone; Standard 15, Oral SABA for symptomatic relief should be used only if no inhaled SABA is available. Adjust to the individual's lowest beneficial dose to minimise adverse effects; Standard 16, Oral leukotriene receptor antagonists (LTRA) can be used as a preventive medication and is preferable to the use of long-term oral systemic corticosteroids; Standard 17, In exceptional circumstances, when there is a high risk of mortality from exacerbations, low-dose oral prednisolone daily or on alternate days may be considered on a case-by-case basis; Standard 18. Oral theophylline should be restricted for use in situations where it is the only bronchodilator treatment option available.CONCLUSION: These first consensus-based clinical standards for asthma management in LMICs are intended to help clinicians provide the most effective care for people in resource-limited settings.

Clinical standards for drug-susceptible TB in children and adolescents

BACKGROUND: These clinical standards aim to provide guidance for diagnosis, treatment, and management of drug-susceptible TB in children and adolescents.METHODS: Fifty-two global experts in paediatric TB participated in a Delphi consensus process. After eight rounds of revisions, 51/52 (98%) participants endorsed the final document.RESULTS: Eight standards were identified: Standard 1, Age and developmental stage are critical considerations in the assessment and management of TB; Standard 2, Children and adolescents with symptoms and signs of TB disease should undergo prompt evaluation, and diagnosis and treatment initiation should not depend on microbiological confirmation; Standard 3, Treatment initiation is particularly urgent in children and adolescents with presumptive TB meningitis and disseminated (miliary) TB; Standard 4, Children and adolescents should be treated with an appropriate weight-based regimen; Standard 5, Treating TB infection (TBI) is important to prevent disease; Standard 6, Children and adolescents should receive home-based/community-based treatment support whenever possible; Standard 7, Children, adolescents, and their families should be provided age-appropriate support to optimise engagement in care and clinical outcomes; and Standard 8, Case reporting and contact tracing should be conducted for each child and adolescent.CONCLUSION: These consensus-based clinical standards, which should be adapted to local contexts, will improve the care of children and adolescents affected by TB.

Isosporosis and unizoite tissue cysts in patients with acquired immunodeficiency syndrome

Isospora belli, a coccidian parasite in humans, has been described as causing chronic diarrhea and acalculous cholecystitis in patients with the acquired immunodeficiency syndrome (AIDS). Diagnosis can be made at the tissue level in the epithelium of the small bowel and by fecal examination. Disseminated extraintestinal forms are uncommon. We studied 118 adult patients with AIDS and chronic diarrhea using stool analysis and endoscopy with duodenal biopsy specimen collection. These samples were processed by routine histology and transmission electron microscopy. Isosporosis was diagnosed in 8 cases. In 2 of them, unizoite tissue cysts were present in the lamina propria, with negative results in stool materials. The cysts were located within a large parasitophorous vacuole. There were no structural means of differentiating the species level of Isospora based on morphology using light or electron microscopy. We believe further work should be done to determine if unizoite tissue cysts are part of the cycle of I belli or of other species of Isospora that could be pathogenic in immunocompromised hosts.

Immunodiagnosis of human fascioliasis by an enzyme-linked immunosorbent assay (ELISA) and a micro-ELISA

Enzyme-linked immunosorbent assay (ELISA) and micro-ELISA were evaluated for their ability to detect anti-Fasciola hepatica antibodies in humans by using excretory-secretory antigen. The sensitivity of each method was 100%, but the specificity was 100% for ELISA and 97% for micro-ELISA. The micro-ELISA could be used as a screening assay and ELISA could be used as a confirmatory method for the serodiagnosis of human fascioliasis.

[Identification of Enterocytozoon bieneusi in a patient with sclerosing cholangitis and AIDS]

Enterocytozoon bieneusi is the most common microsporidian parasite found in patients with AIDS. We report the clinical features of a patient with chronic diarrhea, pancreatitis, and AIDS-related sclerosing cholangitis. Ultrasonography and endoscopic retrograde cholangiopancreatography disclosed intrahepatic and extrahepatic bile duct changes identical to those seen in sclerosing cholangitis. Enterocytozoon bieneusi was found in duodenum and peripapillary duodenum by means of light microscopy, and confirmed by PCR amplification of paraffin-embedded tissues with species-specific primers. Microsporidian infection should be suspected in patients with advanced immunodeficiency and AIDS-related sclerosing cholangitis in our country.

Diagnosis of Enterocytozoon bieneusi by PCR in stool samples eluted from filter paper disks

We report a PCR-based assay for the detection of Enterocytozoon bieneusi. We extracted DNA from feces which had been applied to filter paper disks and evaluated four preserving solutions. Infected specimens were identified by electrophoresis of amplicons from concentrated formalin-fixed samples and unconcentrated fresh feces. Our findings demonstrate that this methodology is effective for sample collection, mailing, and diagnosis of this pathogen.

In situ hybridization: a molecular approach for the diagnosis of the microsporidian parasite Enterocytozoon bieneusi

Microsporidia are emerging as opportunistic pathogens in patients with acquired immunodeficiency syndrome (AIDS). Enterocytozoon bieneusi is the most commonly reported microsporidium that is detected in gastrointestinal specimens. This report describes an in situ hybridization technique with a 30-base specific synthetic DNA probe for detection of E bieneusi by light microscopy. Formalin-fixed paraffin-embedded duodenal biopsy specimens from three patients with AIDS, chronic diarrhea, and E bieneusi infection confirmed by electron microscopy were used in this study. Light microscopic examination after colorimetric detection allowed the identification of different stages of the pathogen's life cycle in the cytoplasm of enterocytes. No cross-reactivity was noted between the probe and human DNA. Our study underscores the applicability of a synthetic-labeled oligonucleotide for the detection and identification of E bieneusi in clinical samples.

[Morphological study of Enterocytozoon bineousi in patients with AIDS and chronic diarrhea]

Microsporidia are protozoan parasites responsible for significant gastrointestinal disease in patients infected with the human immunodeficiency virus. We report the clinical features of three patients with chronic diarrhea and intestinal microsporidiosis caused by Enterocytozoon bieneusi. The average value for CD4 in these patients was < or = 50 cells/mm3. The spores were detected in smears from stool samples and duodenal aspirates stained with trichrome blue in all patients. Light microscopy of semi-thin plastic sections revealed parasites and spores in the enterocytes and were associated with villous atrophy (2 out of 3). Thin section-electron microscopy showed a variety of developmental stages of the microsporidio. Patients treated with Albendazole had an unsatisfactory clinical response to therapy. Enterocytozoon bieneusi infection may be an important cause of diarrhea in patients with AIDS in our country.

[Classic strategies for diagnosis of cryptosporidiosis in patients with AIDS and chronic diarrhea]

Cryptosporidium sp., a protozoa organism, has been increasingly recognized in association with severe enteritis in patients with the Acquired Immunodeficiency Syndrome. The studied subjects included 84 adult patients with AIDS and chronic diarrhea. We describe 14 patients with intestinal infection caused by Cryptosporidium sp. The mean CD4 count in these patients was < or = 300 cells/mm3 (7 out of 14). Examination of duodenal aspirates and feces included dimethylsulfoxide, auramine and acid-fast preparation of concentrated samples. We carried out videoesophagogastroduodenoscopy (VEDA) to visually inspect the mucosa and obtain biopsy specimens. VEDA revealed granular duodenum in ten patients and jasper duodenum in one of them. Duodenal biopsy specimens were stained with hematoxylin-eosin, Giemsa and Azure II. Histologic changes included atrophy (3/14), duodenitis (2/14) or both (3/14). Transmission electron microscopy was used for the identification of developmental stages of Cryptosporidium sp.

Detection of the microsporidian parasite Enterocytozoon bieneusi in specimens from patients with AIDS by PCR

Microsporidia are protozoa parasites responsible for significant gastrointestinal disease in patients infected with human immunodeficiency virus. We evaluated a PCR assay of stool samples, duodenal aspirates, and biopsy specimens from patients with Enterocytozoon bieneusi infection. A 210-bp DNA fragment of the unique rRNA intergenic spacer could be amplified from all samples infected with E. bieneusi, but no amplification was seen by using DNA purified from samples with Septata intestinalis or other parasites and from negative control human cells. These results suggest that the PCR in stool samples may be a useful tool for the diagnosis of intestinal microsporidiosis in patients with AIDS.