Challenges in Diagnosing Primary Ciliary Dyskinesia in a Brazilian Tertiary Hospital

Ultrastructure for the diagnosis of primary ciliary dyskinesia in South Africa, a resource-limited setting

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 resource-limited 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.

Cystic Fibrosis: A Descriptive Analysis of Deaths in a Two-Decade Period in Brazil According to Age, Race, and Sex

The diagnosis of cystic fibrosis has improved in the last few years due to greater access to diagnostic tools and the evolution of molecular biology; the knowledge obtained has contributed to the understanding of its death profile. In this context, an epidemiological study was developed focusing on deaths from cystic fibrosis in Brazil from 1996 to 2019. The data were collected from the Data-SUS (Unified National Health System Information Technology Department from Brazil). The epidemiological analysis included patients' age groups, racial groups, and sex. In our data, between 1996 and 2019, Σ3050 deaths were recorded, totaling a ≅330% increase in the number of deaths resulting from cystic fibrosis. This fact might be related to a better diagnosis of the disease, mainly in patients from racial groups that are not commonly associated with cystic fibrosis, such as Black individuals, Hispanic or Latino (mixed individuals/Pardos) individuals, and American Indians (Indigenous peoples from Brazil). Regarding of race, the Σ of deaths was: nine (0.3%) in the American Indian group, 12 (0.4%) in the Asian group, 99 (3.6%) in the Black or African American group, 787 (28.6%) in the Hispanic or Latino group, and 1843 (67.0%) in the White group. The White group showed the highest prevalence of deaths, and the increase in mortality was ≅150 times in this group, while, in the Hispanic or Latino group, it was ≅75 times. Regarding sex, the numbers and percentage of deaths of both male (N = 1492; 48.9%) and female (N = 1557; 51.1%) patients were seen to be relatively close. As for age groups, the >60-year-old group presented the most significant results, with an increase of ≅60 times in the registered deaths. In conclusion, in Brazil, despite the number of deaths from cystic fibrosis being prevalent in the White group, it increased in all racial groups (Hispanic or Latino, Black or African American, American Indian, or Asian individuals) and was associated with older age.