MATERIALS AND METHODS
We conducted a retrospective study, including all patients with CF who
were registered and followed between April 2000 and April 2020 in the CF
Center at University Hospital (Dr. José E. González in Monterrey
Mexico). Demographic, clinical, and biological variables were
documented, such as gender sex, age at diagnosis, SES, pancreatic
status, CFTR genotypes, and diagnosis of chronic infection with P.
aeruginosa at 6 years. Age at diagnosis was categorized as ≤ 2 years, 3
– 18 years, > 18 years. SES was evaluated using the
Asociación Mexicana de Agencias de Inteligencia de Mercado y Opinion
(AMAI) score, with patients divided in high (AB, C+, and C) and low
socioeconomic levels (C,D, and E)16. A
pancreatic-insufficient or pancreatic-sufficient classification was
based on enzyme usage.2 Genotype was classified as
homozygous for F508Δ mutation, heterozygous for F508Δ mutation, and
other or missing. Quarterly sputum or oropharyngeal swab bacteriology in
the first 6 years were evaluated to detect chronic infection withP. aeruginosa, using Leeds Criteria.17
The Mexican health system is complex; it is comprised of two sectors:
public and private. The public sector includes: (1) Social security
institutions [Instituto Mexicano del Seguro Social (IMSS), Instituto
de Seguridad y Servicios Sociales de los Trabajadores del Estado
(ISSSTE), Petróleos Mexicanos (PEMEX), Ministry of Defense (SEDENA),
Ministry of the Navy (SEMAR), and (2) programs that cover the population
without social security [Ministry of Health (SSa), State Health
Services (SESA), IMSS-Oportunidades (IMSS-O), Seguro Popular (SPS)].
The private sector is comprised of insurance companies and service
providers, working in both private clinics and
hospitals.18 Access to tobramycin varies according to
health coverage; currently, patients belonging to ISSSTE, PEMEX, SEDENA
SEMAR, SPS, and the majority of patients from private health insurance
companies have access to this drug.
This study was approved by the Institutional Research Ethics Committee.