Monica Birkhead - Academia.edu (original) (raw)
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Papers by Monica Birkhead
Tropical Medicine and Infectious Disease, 2018
Two cases of cryptococcal meningitis went undetected by a cryptococcal antigen (CrAg) lateral flo... more Two cases of cryptococcal meningitis went undetected by a cryptococcal antigen (CrAg) lateral flow assay on blood in a reflex CrAg screen-and-treat programme in South Africa, although Cryptococcus neoformans was identified by culturing the cerebrospinal fluid specimens. Further investigations into these discordant diagnostic results included multilocus sequence typing (which showed no mutations in the CAP59 gene) and transmission electron microscopy using a capsule-staining protocol (which revealed a >50% reduction in capsular material in both cases, relative to a control culture). A multi-disciplinary approach for resolving discordant diagnostic test results is recommended.
Front. Pediatr. 11:1247638., 2023
Introduction: International guidelines recommend a multi-faceted approach for successful diagnose... more Introduction: International guidelines recommend a multi-faceted approach for successful diagnoses of primary ciliary dyskinesia (PCD). In the absence of a gold standard test, a combination of genetic testing/microscopic analysis of structure and function/nasal nitric oxide measurement is used. In resourcelimited settings, often none of the above tests are available, and in South Africa, only transmission electron microscopy (TEM) is available in central anatomical pathology departments. The aim of this study was to describe the clinical and
ultrastructural findings of suspected PCD cases managed by pediatric
pulmonologists at a tertiary-level state funded hospital in Johannesburg.
Methods: Nasal brushings were taken from 14 children with chronic respiratory symptoms in keeping with a PCD phenotype. Ultrastructural analysis in accordance with the international consensus guidelines for TEM-PCD diagnostic reporting was undertaken.
Results: TEM observations confirmed 43% (6) of the clinically-suspected
cases (hallmark ultrastructural defects in the dynein arms of the outer
doublets), whilst 57% (8) required another PCD testing modality to support
ultrastructural observations. Of these, 25% (2) had neither ultrastructural
defects nor did they present with bronchiectasis. Of the remaining cases, 83% (5) had very few ciliated cells (all of which were sparsely ciliated), together with goblet cell hyperplasia. There was the apparent absence of ciliary rootlets in
17% (1) case. Discussion: In resource-limited settings in which TEM is the only available testing modality, confirmatory and probable diagnoses of PCD can be made to facilitate early initiation of treatment of children with chronic respiratory symptoms.
Tropical Medicine and Infectious Disease, 2018
Two cases of cryptococcal meningitis went undetected by a cryptococcal antigen (CrAg) lateral flo... more Two cases of cryptococcal meningitis went undetected by a cryptococcal antigen (CrAg) lateral flow assay on blood in a reflex CrAg screen-and-treat programme in South Africa, although Cryptococcus neoformans was identified by culturing the cerebrospinal fluid specimens. Further investigations into these discordant diagnostic results included multilocus sequence typing (which showed no mutations in the CAP59 gene) and transmission electron microscopy using a capsule-staining protocol (which revealed a >50% reduction in capsular material in both cases, relative to a control culture). A multi-disciplinary approach for resolving discordant diagnostic test results is recommended.
Front. Pediatr. 11:1247638., 2023
Introduction: International guidelines recommend a multi-faceted approach for successful diagnose... more Introduction: International guidelines recommend a multi-faceted approach for successful diagnoses of primary ciliary dyskinesia (PCD). In the absence of a gold standard test, a combination of genetic testing/microscopic analysis of structure and function/nasal nitric oxide measurement is used. In resourcelimited settings, often none of the above tests are available, and in South Africa, only transmission electron microscopy (TEM) is available in central anatomical pathology departments. The aim of this study was to describe the clinical and
ultrastructural findings of suspected PCD cases managed by pediatric
pulmonologists at a tertiary-level state funded hospital in Johannesburg.
Methods: Nasal brushings were taken from 14 children with chronic respiratory symptoms in keeping with a PCD phenotype. Ultrastructural analysis in accordance with the international consensus guidelines for TEM-PCD diagnostic reporting was undertaken.
Results: TEM observations confirmed 43% (6) of the clinically-suspected
cases (hallmark ultrastructural defects in the dynein arms of the outer
doublets), whilst 57% (8) required another PCD testing modality to support
ultrastructural observations. Of these, 25% (2) had neither ultrastructural
defects nor did they present with bronchiectasis. Of the remaining cases, 83% (5) had very few ciliated cells (all of which were sparsely ciliated), together with goblet cell hyperplasia. There was the apparent absence of ciliary rootlets in
17% (1) case. Discussion: In resource-limited settings in which TEM is the only available testing modality, confirmatory and probable diagnoses of PCD can be made to facilitate early initiation of treatment of children with chronic respiratory symptoms.