Differential diagnoses of severe COVID‐19 in tropical areas: the experience of Reunion Island

Abstract

Objective To identify the differential diagnoses of severe COVID‐19 and the distinguishing characteristics of critically ill COVID‐19 patients in Reunion Island to help improve the triage and management of patients in this tropical setting. Methods This retrospective observational study was conducted from 11 March to 4 May 2020 in the only intensive care unit (ICU) authorised to manage COVID‐19 patients in Reunion Island, a French overseas department located in the Indian Ocean region. All patients with unknown COVID‐19 status were tested by polymerase chain reaction (PCR) on ICU admission; those who tested negative were transferred to the COVID‐19‐free area of the ICU. Results Over the study period, 99 patients were admitted to our ICU. A total of 33 patients were hospitalised in the COVID‐19 isolation ward, of whom 11 were positive for COVID‐19. The main differential diagnoses of severe COVID‐19 were as follows: community‐acquired pneumonia, dengue, leptospirosis causing intra‐alveolar haemorrhage and cardiogenic pulmonary oedema. The median age of COVID‐19‐positive patients was higher than that of COVID‐19‐negative patients (71 [58–74] vs. 54 [46–63.5] years, P = 0.045). No distinguishing clinical, biological or radiological characteristics were found between the two groups of patients. All COVID‐19‐positive patients had recently travelled or been in contact with a recent traveller. Conclusions In Reunion Island, dengue and leptospirosis are key differential diagnoses of severe COVID‐19, and travel is the only distinguishing characteristic of COVID‐19‐positive patients. Our findings apply only to the particular context of Reunion Island at this time of the epidemic.

Differentiating COVID-19 and dengue from other febrile illnesses in co-epidemics: Development and internal validation of COVIDENGUE scores

“…The COVIDENGUE scores were developed using MLR [ 9 ] which is the gold standard method for assessing non-ordered polytomous categorical outcomes [ 27 , 28 ]. Except for active smoking whose protective effect against SARS-CoV-2 infection remains a matter of debate among researchers [ 29 , 30 ], all predictors retained to build the scores had been previously identified as relevant indicators of COVID-19 or dengue or associated with OFIs (especially respiratory infections) [ [31] , [32] , [33] , [34] , [35] , [36] , [37] , [38] , [39] , [40] , [41] , [42] , [43] ] This ensures both the validity of content of this scoring system and the possibility of contrasted predictions. For example, international travel had been identified as a source of COVID-19 during the first pandemic wave [ [36] , [37] , [38] ].…”

“…The COVIDENGUE scores were developed from data acquired within a hospital-based SARS-CoV-2 testing center on Reunion Island which is a tropical setting where dengue co-circulated early on during the first pandemic wave at a time when there was no possibility to screen for COVID-19 outside the hospital. The circulation of the SARS-CoV-2 variant was furthermore unknown and the population of infected people were mainly composed of relatively healthy travelers [ 9 , 37 , 38 ]. Thus, although our center served an ambulatory healthcare driven population, the scores will have to be validated in primary care settings before being broadly used in the community.…”

“…Thus, although our center served an ambulatory healthcare driven population, the scores will have to be validated in primary care settings before being broadly used in the community. They will also have to be validated in the highly comorbid autochthonous population of the island [ 9 , 37 , 38 ].…”

Differentiating COVID-19 and dengue from other febrile illnesses in co-epidemics: Development and internal validation of COVIDENGUE scores

“…Except for active smoking whose protective effect against SARS-CoV-2 infection remains a matter of debate among researchers [28,29], all predictors retained to build the scores had been previously identified as relevant indicators of COVID-19 or dengue or associated with OFIs (especially respiratory infections) [29][30][31][32][33][34][35][36][37][38][39][40] This ensures both the validity of content of this scoring system and the possibility of contrasted predictions. For example, international travel had been identified as a source of COVID-19 during the first pandemic wave [34,35]. In a recent Colombian study [38], dengue proved more symptomatic than COVID-19 and dengue patients came to the hospital in greater numbers than COVID-19 patients.…”

“…The COVIDENGUE scores were developed using MLR [9] which is the gold standard method for assessing non-ordered polytomous categorical outcomes [26,27]. Except for active smoking whose protective effect against SARS-CoV-2 infection remains a matter of debate among researchers [28,29], all predictors retained to build the scores had been previously identified as relevant indicators of COVID-19 or dengue or associated with OFIs (especially respiratory infections) [30][31][32][33][34][35][36][37][38][39][40][41][42] This ensures both the validity of content of this scoring system and the possibility of contrasted predictions. For example, international travel had been identified as a source of COVID-19 during the first pandemic wave [35][36][37].…”