ОПРЕДЕЛЕНИЕБолезнь Гоше (БГ) -наиболее частая форма наследственных ферментопатий, объединенных в группу лизосомных болезней накопления, в основе которой лежит дефект гена GBA, кодирующего лизо-сомный фермент -D-глюкозидазу (глюкоцеребрози-дазу), ответственный за катаболизм липидов.Код МКБ-10 Е75.2 Другие сфинголипидозы.
ЭПИДЕМИОЛОГИЯЧастота БГ составляет 1:40 000-1:70 000. В популя-ции евреев-ашкенази (выходцев из Восточной Европы) частота встречаемости этого заболевания является более высокой и достигает 1:450-1:1000. ЭТИОПАТОГЕНЕЗ БГ наследуется по аутосомно-рецессивному типу. Присутствие двух мутантных аллелей гена GBA ассоции-руется со значительным (р 30% от нормального уровня)
Laboratory diagnostics of lysosomal acid lipase deficiency (LAL‐D), a rare disorder associated with
LIPA
alterations, are based on the evaluation of LAL activity. In dry blood spots (DBS) submitted for LAL‐D diagnostics (the screening cohort) over a two‐year period or obtained from a cohort of retrospective LAL‐D patients, we measured: (1) LAL activity using a two‐reaction assay with 4‐methylumbelliferone palmitate (4‐MU‐Palm) and Lalistat‐2, a specific LAL inactivator; (2) total lipase (TL) activity by a 1‐hour kinetic 4‐MU‐Palm cleavage reaction (no Lalistat‐2). The TL activity was expressed as the area under the kinetic curve after 1 hour (TL‐AUC
1h
) of the reaction and presented as the median (min‐max). LAL activity was reduced in 30/537 individuals from the screening cohort, among which
LIPA
sequencing revealed six patients and one carrier. Overall, 16 (89%) individuals among six novel and 12 retrospective LAL‐D patients carried at least one c.894G>A mutation (six were homozygous). The TL‐AUC1h in nonLAL‐D specimens with normal LAL activity (n = 90) was unambiguously higher (9471 [4015‐23 585] RFU*h/punch) compared to LAL‐D patients, including six new and nine retrospective patients (1810 [357‐2608] RFU*h/punch). Importantly, in 13/15 examined nonLAL‐D specimens with reduced LAL activity the TL‐AUC1h was above a threshold of 2652 RFU*h/punch. Applying this threshold, the TL‐AUC1h index discriminated all LAL‐D patients (100% sensitivity) and 103/105 nonLAL‐D specimens (98% specificity). Given that there is no need for Lalistat‐2 and two parallel enzymatic reactions in conjunction with high sensitivity and specificity, the kinetic assay seems to be practical for LAL‐D screening.
Synopsis
Lysosomal acid lipase deficiency responsible for Wolman disease and cholesterol ester storage disease could be reliably detected using a kinetic assay of total lipase activity with a fluorogenic substrate.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.