Abstract
Objective of our study was to determine the clinical characteristics and laboratory profile of scrub typhus patients requiring pediatric intensive care admission and to find out risk factors for the severity of illness. This was a cross-sectional observational study conducted on 1-month to 12-year-old children admitted with scrub typhus in a tertiary care pediatric intensive care unit (PICU). Relevant demographic, clinical, laboratory, treatment, and outcome-related data were documented. The severity of the disease was measured in the form of multiple organ dysfunction syndrome (MODS). With further correlation, and univariate and multivariate analyses, factors associated with severe disease were identified. During the study period, out of 586 PICU admission, 62 patients (10.6%) were diagnosed with scrub typhus. The mean age was 63.85 ± 52.78 months, where infants constituted 32.3% of the total population. Fever was present in 100% of the cases. Common indications of PICU admission were: respiratory distress 42 (67.7%), altered sensorium 41 (66.1%), convulsion 37 (59.7%), and shock 31 (50%). Total number of patients with MODS was 40 (64.5%). The case fatality rate was 8%. On multivariate analysis, infant age group ( p = 0.02), altered sensorium ( p = 0.001), reduced urine output ( p = 0.02), thrombocytopenia ( p = 0.001), raised C-reactive protein ( p = 0.004), hyponatremia ( p = 0.005), hypoalbuminemia ( p = 0.01), deranged international normalized ratio ( p = 0.02), and hyperferritinemia ( p = 0.02) came out to be independent factors in predictability for development of MODS. Multiorgan dysfunction is a life-threatening manifestation of scrub typus in children, which necessitates PICU admission. Infant age group, presence of altered sensorium, reduced urine output, thrombocytopenia, elevated inflammatory markers, coagulopathy, hypoalbuminemia, and hyponatremia predict risk for MODS.
Keywords: scrub typhus, severe disease, pediatric intensive care unit, risk factors
Introduction
Scrub typhus is an acute febrile illness caused by Orientia tsutsugamushi prevalent in Southeast Asia, which causes varied clinical presentation. Scrub typhus was grossly underdiagnosed in India due to several limitations in the past. Some of them were nonspecific clinical presentation, lack of awareness, low index of suspicion, and lack of diagnostic facilities. 1 2 However, the emergence of this infection in epidemic proportions has increased the awareness among clinicians for scrub typhus as a not so uncommon diagnosis. For the past one decade, there have been several published reports from various geographical regions, which has made scrub typhus a pan-India phenomenon. Whatsoever, early diagnosis remains challenging because of nonspecific and a varied clinical picture. The fatal progress to multiple organ dysfunction syndrome (MODS) unless intervened early has been alarming and raises a concern to identify risk factors associated with severe disease and unfavorable outcomes.
Severe scrub typhus disease associated with different organ involvement usually needs intensive care. They need meticulous monitoring and timely intervention to avoid untoward outcome. Therefore, screening of the clinically accessible risk factors is most relevant to predict the severity of the disease. This may provide a comprehensive basis for the clinical assessment of prognosis and guidance for the requirement of intensive care unit (ICU) care and give us an excellent outcome and recovery. Based on these factors, severe disease-prone patients can be admitted earlier to a hospital or transferred to a well-equipped institution. Close observation and intensive care can prevent complications and severe morbidity or mortality.
This present study was undertaken in view of the increased incidence of pediatric population being diagnosed with scrub typhus and requiring intensive care during illness as a consequence of multiorgan involvement. 3 4 5
Aims and Objective
To determine the clinical characteristics and laboratory profile of scrub typhus patients requiring pediatric intensive care admission and to find out risk factors for the severity of illness in the form of multiorgan failure.
Material and Method
This was a prospective observational study conducted at the pediatric ICU (PICU) of a tertiary care hospital from August 2018 to September 2019. The patients were included in the study after taking informed consent from their parents/guardians in their understandable language. The study was approved by the Ethical Committee of the Institute.
Children in the age group of 1 month to 12 years with scrub typhus were included in the study. Patients with comorbidities and preexisting illnesses were excluded. According to Integrated Disease Surveillance Programme definition (2019), clinical case of scrub typhus is defined as: Acute undifferentiated febrile illness of 5 days or more with or without eschar (if eschar is present, fever of less than 5 days duration should be considered as scrub typhus). 6 Cases fulfilling these criteria were taken as suspect, and thereafter positive scrub typhus immunoglobulin M (IgM) enzyme-linked immunosorbent assay (ELISA; optical density > 0.5) was defined as a probable case as per the definition of Indian Council of Medical Research. 7 Additionally, blood culture, urine culture, malaria rapid diagnostic test, thick and thin smear for malaria, leptospiral serology, dengue IgM by ELISA, serologic and/or nucleic acid-based diagnostic testing for Epstein-Barr virus, serological testing for human immunodeficiency virus, hepatitis B and C, and mycoplasma pneumonia, and Widal tests were performed based on the clinical presentation and suspected etiology.
Detailed history and physical findings were noted in all cases. Demographic profiles like age and sex were recorded. Clinical features like fever, malnutrition, rash, eschar, organomegaly, respiratory distress, shock, altered sensorium, and bleeding manifestation were noted. Laboratory investigations like complete hemogram, serum ferritin, coagulation profile, liver function tests, C-reactive protein (CRP), procalcitonin, fibrinogen, cerebrospinal fluid (CSF) cell count and protein, and serum creatinine were measured. The cut-off for hematological parameters were defined as anemia (hemoglobin less than 9 g/dL), thrombocytopenia (platelet ≤ 1.0 × 10 5 /mm 3 ), leukopenia (white blood cell [WBC] less than 4,500/mm 3 ), and leukocytosis (WBC > 12,000/mm 3 ).
The cut-off values for other laboratory markers were taken as: high procalcitonin (> 2 ng/mL), hyperferritinemia (>10,000 ng/mL), 8 hypoalbuminemia (<2.5 mg/dL), raised creatinine (> upper limit of normal for age), raised CRP (>10 g/L), raised alanine aminotransferase/serum glutamic-pyruvic transaminase (ALT/SGPT: ≥ 80 IU/l), hypofibrinogenemia (<150 mg/dL), deranged international normalized ratio (INR; > 1.5), and hyponatremia (<135 mEq/L).
Treatment received in the form of mechanical ventilation, normal saline bolus and inotropes, management of raised intracranial pressure, blood product transfusion, and renal replacement therapy were noted. Treatment-related variables, organ supportive therapies, and outcome parameters were studied based on duration of PICU stay, time for defervescence, hospital stay, mortality, inotrope requirement as expressed by vasoactive inotrope score (VIS), 9 and duration of mechanical ventilation.
The criteria for MODS, 10 11 acute respiratory distress syndrome (ARDS), 12 acute kidney injury (AKI), 13 and hemophagocytic lymphohistiocytosis (HLH) 14 were defined according to standard guidelines. A comparison of clinical characteristic and laboratory profile was done between MODS and non-MODS cases to identify risk factors of severe disease.
A well-designed proforma containing various parameters under study was used for data collection. The data were maintained in Microsoft Excel. SPSS software version 26 was used for the statistical analysis of the data. Categorical data were analyzed in terms of number, percentage, and ratios.
Quantitative data were expressed as mean (standard deviation), ratio. Quantitative continuous variables were compared between groups using Mann–Whitney's nonparametric tests if the variable had a nonnormal distribution and unpaired t -test if the variable had a normal distribution. Qualitative variables were compared by the chi-squared test (χ 2 ) and Fischer's exact test. A two-sided p -value < 0.05 was considered statistically significant for all tests. Severity-based categorization into MODS and non-MODS was done, which was then put through univariate followed by multivariate analysis to identify independent predictors of severity and outcome.
Results
During the study period, 586 patients required PICU admission, out of which 62 cases (10.6%) were diagnosed with scrub typhus. Majority were male and above 5 years of age. Fever was present in 100% of the cases, with an average duration of 10.89 ± 6.39 days. Common indications of admission were: respiratory distress 42 (67.7%), followed by altered sensorium 41 (66.1%), convulsion 37 (59.7%), and shock 31 (50%; Table 1 ).
Table 1. Demographic profile and clinical features.
| Variables | Total cases: n = 62 |
|---|---|
| Age (in months): mean ± SD | 63.85 ± 52.78 |
| Age < 1 year: n (%) | 20 (32.3) |
| Age > 5 years: n (%) | 32 (51.6) |
| Male: n (%) | 36 (58.1) |
| Malnutrition: n (%) | 10 (16.1) |
| Variables | |
| Fever: n (%) | 62 (100) |
| Duration of fever (in days): mean ± SD | 10.89 ± 6.39 |
| Fever ≤ 7 days: n (%) | 18 (29.1) |
| Fever > 7 days: n (%) | 44 (70.9) |
| Respiratory distress: n (%) | 42 (67.7) |
| Altered sensorium: n (%) | 41 (66.1) |
| Convulsion: n (%) | 37 (59.7) |
| Shock: n (%) | 31 (50) |
| Pain abdomen: n (%) | 21 (33.9) |
| Vomiting: n (%) | 17 (27.4) |
| Eschar: n (%) | 9 (14.5) |
| Bleeding: n (%) | 15 (24.2) |
| Lymphadenopathy: n (%) | 13 (21) |
| Hepatomegaly: n (%) | 41 (66.1) |
| Splenomegaly: n (%) | 36 (58.1) |
| Oliguria: n (%) | 18 (29) |
Abbreviation: SD, standard deviation.
Major complications found in our study population were shock ( n = 31; 50%) followed by meningoencephalitis (32; 51.6%; Table 2 ).
Table 2. Complications.
| Variables | Total cases: n = 62 |
|---|---|
| Shock, n (%) | 31 (50) |
| Pneumonia, n (%) | 19 (30.6) |
| ARDS, n (%) | 6 (9.7) |
| AKI, n (%) | 22 (35.5) |
| Acute liver failure, n (%) | 3 (4.8) |
| Meningoencephalitis, n (%) | 32 (51.6) |
| Myocarditis, n (%) | 3 (4.8) |
| Pleural effusion, n (%) | 6 (9.7) |
| DIC, n (%) | 4 (6.5) |
| HLH, n (%) | 7 (11.3) |
Abbreviations: ARDS, acute respiratory distress syndrome; AKI, acute kidney injury; DIC, disseminated intravascular coagulation; HLH, hemophagocytic lymphohistiocytosis.
The hematological parameters studied in the population showed anemia in 62.9% cases ( n = 39), thrombocytopenia in 48.4% cases ( n = 30), and leukocytosis in 66.1% cases ( n = 41). CRP was elevated in 82.3% cases ( n = 51). Alanine transaminase was raised in 38.7% patients ( n = 24).
Among the inflammatory markers, high procalcitonin was found in 21% cases ( n = 13), hyperferritinemia in 12.9% cases ( n = 8), hypofibrinogenemia in 67.7% cases ( n = 42), and hypoalbuminemia in 14.5% cases ( n = 9). The cut-off values are taken as of our institute. Raised creatinine at day 1 of admission was seen in 35.5% of cases. INR was above normal in 16 cases.
CSF pleocytosis and elevated CSF protein were seen in 9 and 12 out of 32 cases of meningoencephalitis, respectively ( Table 3 ).
Table 3. Laboratory parameters.
| Variables | Total cases: n = 62 | Mean | Standard deviation |
|---|---|---|---|
| Hemoglobin ≤9 g/dL: n (%) | 39 (62.9) | 8.82 | 1.71 |
| Total leukocyte count > 12*10 3 /mm 3 : n (%) | 41 (66.1) | 19,909.84 | 15,405.24 |
| Total platelet count ≤ 1.0*10 5 /mm 3 : n (%) | 30 (48.4) | 140,129.03 | 107,758.45 |
| CRP >10 g/L: n (%) | 51 (82.3) | 61.23 | 40.95 |
| ALT/SGPT > 80 IU/L: n (%) | 24 (38.7) | 76.56 | 46.32 |
| Procalcitonin > 2 ng/mL: n (%) | 13 (21) | 6.44 | 12.02 |
| Ferritin ≥ 10,000 ng/mL: n (%) | 8 (12.9) | 3,629.56 | 9,149.92 |
| Fibrinogen < 150 mg/dL: n (%) | 42 (67.7) | 215.73 | 254.04 |
| Albumin < 2.5 g/dL: n (%) | 9 (14.5) | 3.34 | 0.59 |
| Raised creatinine: n (%) | 22 (35.5) | 0.50 | 0.19 |
| INR > 1.5: n (%) | 16 (25.8) | 1.45 | 1.16 |
| Serum sodium < 135 mEq/L: n (%) | 37 (59.6) | 133.4 | 4.9 |
| CSF pleocytosis: n (%) | 9 out of 32 (28.1) | – | – |
| CSF protein elevated: n (%) | 12 out of 32 (37.5) | – | – |
Abbreviations: ALT/SGPT, alanine aminotransferase/serum glutamic-pyruvic transaminase; CRP, C-reactive protein; CSF, cerebrospinal fluid; INR, international normalized ratio.
We have treated all the patients with intravenous doxycycline at 4 mg/kg/day in two divided doses; mechanical ventilation was required in 54.8% cases ( n = 34), fluid bolus was administered in 51.6 % cases ( n = 32), and inotrope was required in 45.2% cases ( n = 28). Mean duration of PICU stay was 3.73 ± 3.29 days, while average duration of mechanical ventilation required was 2.26 ± 3.48 days.
VIS was 12.85 ± 21.09 and mean fluid bolus requirement was 15.48 ± 18.08 mL/kg in the study population. The overall mortality rate was 8% ( n = 5). Immunomodulator therapy was required in three out of seven cases of HLH. Intravenous immunoglobulin was used as first-line immunomodulator, which was administered in three patients. One patient was nonresponder to immunoglobulin and methylprednisolone was added to the regimen. The average time of defervescence for all the patients was 2 ± 0.88 days. Mean duration of in-hospital stay was 8.52 ± 4.8 days. While making a comparison between MODS and non-MODS group, we have found a significant variation in average duration of PICU stay ( p < 0.001), average requirement of fluid bolus ( p = 0.004), requirement of inotrope ( p = 0.002), average VIS ( p = 0.02), requirement ( p = 0.000) and mean duration ( p = 0.000) of mechanical ventilation, need for immunotherapy ( p = 0.000), mean duration for defervescence ( p = 0.000), and average duration of hospital stay ( p = 0.000; Table 4 ).
Table 4. Treatment and severity parameters.
| Variables | Total cases ( n = 62) | MODS (40) | Non-MODS (22) | p -Value |
|---|---|---|---|---|
| Duration of PICU stay (in days): mean ± SD | 3.73 ± 3.29 | 5.05 ± 3.41 | 1.32 ± 0.56 | <0.001 |
| Requirement of fluid bolus: n (%) | 32 (51.6) | 24 (60) | 8 (36.4) | 0.07 |
| Average requirement of fluid bolus (mL/kg): mean ± SD | 15.48 ± 18.08 | 20.25 ± 19.67 | 6.82 ± 10.41 | 0.004 |
| Requirement of inotrope: n (%) | 28 (45.2) | 24 (60) | 4 (18.2) | 0.002 |
| Average vasoactive inotropic score: mean ± SD | 12.85 ± 21.09 | 17.25 ± 23.7 | 4.86 ± 11.8 | 0.02 |
| Requirement of mechanical ventilation: n (%) | 34 (54.8) | 34 (85) | 0 | 0.000 |
| Average duration of mechanical ventilation (in days): mean ± SD | 2.26 ± 3.48 | 3.5 ± 3.8 | 0 | 0.000 |
| Osmotherapy for raised ICP (3% NaCl): n (%) | 12 (19) | 10 (25) | 2 (9.1) | 0.12 |
| Requirement of blood products: n (%) | 16 (25.8) | 12 (30) | 4 (18.2) | 0.3 |
| Doxycycline: n (%) | 62 (100) | – | – | – |
| Immunotherapy: n (%) | 3 (4.8) | 3 (7.5) | 0 | 0.000 |
| Time for defervescence (in days): mean ± SD | 2.0 ± 0.88 | 2.2 ± 0.85 | 1.09 ± 0.29 | 0.000 |
| Duration of hospital stay (in days): mean ± SD | 8.52 ± 4.8 | 10.4 ± 5 | 5.09 ± 0.6 | 0.000 |
Abbreviations: ICP, intracranial pressure; MODS, multiple organ dysfunction syndrome; NaCl, sodium chloride; PICU, pediatric intensive care unit; SD, standard deviation.
Total number of patients with MODS was 40 (64.5%). We lost five patients to MODS and the rest of the cases were successfully discharged. On univariate analysis we observed that infant age group, altered sensorium, reduced urine output, moderate anemia, leukocytosis, thrombocytopenia, raised CRP, hyponatremia, hypoalbuminemia, raised ALT/SGPT, deranged INR, and hyperferritinemia showed significant association with MODS. On further multivariate analysis, infant age group ( p = 0.02), altered sensorium ( p = 0.001), reduced urine output ( p = 0.02), thrombocytopenia ( p = 0.001), raised CRP ( p = 0.004), hyponatremia ( p = 0.005), hypoalbuminemia ( p = 0.01), deranged INR ( p = 0.02), and hyperferritinemia ( p = 0.02) came out to be independent factors in predictability for development of MODS ( Table 5 ).
Table 5. Correlation of clinical and laboratory parameters with multiple organ dysfunction syndrome.
| Variables (total cases = 62) | MODS (40): n (%) | Non- MODS (22): n (%) | Odds ratio (95% CI) | Significance ( p -Value; univariate analysis) | Correlation (multivariate analysis) | p -Value (multivariate analysis) |
|---|---|---|---|---|---|---|
| Age < 1 year | 11 (33) | 2 (9) | 4.81 (0.91–27.37) | 0.03 | 0.51 | 0.02 |
| Malnutrition | 8 (20) | 2 (9.1) | 2.5 (0.43–26.16) | 0.229 | – | – |
| Fever > 7 days | 28 (70) | 16 (72.7) | 0.88 (0.22–3.15) | 0.531 | – | – |
| Respiratory distress | 28 (70) | 14 (63.6) | 1.33 (0.38–4.55) | 0.406 | – | – |
| Shock | 22 (55) | 9 (40.9) | 1.77 (0.55–5.82) | 0.213 | – | – |
| Convulsion | 27 (67.5) | 10 (45.5) | 2.49 (0.75–8.30) | 0.078 | – | – |
| Altered sensorium | 31 (77.5) | 10 (45.5) | 4.13 (1.17–14.69) | 0.012 | 0.76 | 0.001 |
| Bleeding manifestation | 12 (30) | 3 (13.6) | 2.71 (0.61–16.74) | 0.128 | – | – |
| Hepatomegaly | 25 (62.5) | 16 (72.7) | 0.63 (0.16–2.19) | 0.299 | – | – |
| Splenomegaly | 22 (55) | 14 (63.6) | 0.70 (0.21–2.29) | 0.350 | – | – |
| Reduced urine output | 15 (37.5) | 3 (13.6) | 3.80 (0.87–22.94) | 0.042 | 0.63 | 0.02 |
| Eschar | 6 (15) | 3 (13.6) | 1.12 (0.21–7.68) | 0.601 | – | – |
| Pain abdomen | 7 (17.5) | 14 (63.6) | 0.12 (0.03–0.46) | – | –0.78 | – |
| Hemoglobin ≤ 9 g/dL | 31 (77.5) | 8 (36.4) | 6.03 (1.68–22.14) | 0.002 | 0.38 | 0.06 |
| Total leukocyte count > 12*10 3 /mm 3 | 31 (77.5) | 10 (45.5) | 4.13 (1.17–14.69) | 0.012 | 0.32 | 0.07 |
| Total platelet Count ≤ 1.0*10 5 /mm 3 | 25 (62.5) | 5 (22.7) | 5.67 (1.54–23.19) | 0.003 | 0.72 | 0.001 |
| CRP > 10 g/L | 37 (92.5) | 14 (63.6) | 7.05 (1.39–45.49) | 0.007 | 0.66 | 0.004 |
| Ferritin ≥10,000 ng/mL | 8 (20) | 0 | – | 0.023 | 0.58 | 0.02 |
| ALT/SGPT > 80 IU/L | 24 (60) | 6 (27.3) | 4.00 (1.15–14.98) | 0.013 | 0.31 | 0.08 |
| Fibrinogen < 150 mg/dL | 23 (57.5) | 19 (86.4) | 0.21 (0.04–0.92) | – | –0.295 | – |
| Raised creatinine | 17 (42.5) | 5 (22.7) | 2.5 (0.69–10.33) | 0.099 | – | – |
| Deranged INR (>1.5) | 14 (35) | 2 (9.1) | 5.38 (1.02–52.98) | 0.023 | 0.28 | 0.02 |
| Albumin < 2.5 g/dL | 9 (22.5) | 0 | – | 0.013 | 0.3 | 0.01 |
| Hyponatremia (serum sodium less than 135 mEq/L) | 29 (72.5) | 8 (36.4) | 4.61 (1.33–16.33) | 0.006 | 0.45 | 0.005 |
| Mortality: n (%) | 5 (12.5) | 0 | – | 0.102 | – | – |
Abbreviations: ALT/SGPT, alanine aminotransferase/serum glutamic-pyruvic transaminase; CI, confidence interval; CRP, C-reactive protein; INR, international normalized ratio; MODS, multiple organ dysfunction syndrome.
Discussion
In our study, we have treated 62 cases of scrub typhus in PICU among which 40 cases were identified as MODS. We observed that fever was universally present in all the cases. A similar observation was made in other studies. 15 16 17 18 Common indications of PICU admission in our study population were respiratory distress, altered sensorium, convulsion, and shock. A recent retrospective observational study from North India has published that the presence of lymphadenopathy, respiratory distress, shock, elevated lactate, and meningoencephalitic presentation emerged as independent predictors for the need of intensive care. 19
Scrub typhus is an acute febrile illness with varied clinical presentations. It can involve different organs in its severe form but pneumonia (20–35%) and meningoencephalitis (10%) are more common. 20 In the worst scenario, it may lead to ARDS. 3 21 22 If left undiagnosed and untreated, case fatality rate may be as high as 30%. 3 20 Widespread endothelial injury leads to distributive shock in the second week of illness. Sometimes acute fulminant myocarditis may lead to cardiogenic shock. 23 Indian literature has reported quite a high rate of central nervous system involvement, 24 25 AKI, requirement of renal replacement therapy, 26 thrombocytopenia, disseminated intravascular coagulation, 15 27 and HLH. 28
We have found a significant association of altered sensorium and reduced urine output with the development of MODS during the course of illness. Infant age group was noted as significant risk factor for severe disease. No previous study mentions about infant age group as a risk factor for severity of scrub typhus, which may be due to the perception that infants are seldom affected owing to absence of outdoor activity, thus making early suspicion and diagnosis very difficult.
A prospective study of 66 children with scrub typhus in North India 16 and another study by Gurunathan et al 29 in the pediatric cohort also reported varied clinical presentation and subsequent complications in the form of meningoencephalitis, MODS, and AKI, and bleeding manifestations, respectively. Meena et al 30 published a case series of 49 cases of scrub typhus where, unlike our study, the incidence of ARDS, AKI, and shock were relatively lower. Intensive care was needed in 20% of patients with an incidence of MODS and mortality being 8% patients and 4% patients, respectively.
The presence of anemia, thrombocytopenia, raised CRP, hyponatremia, hypoalbuminemia, deranged INR, and hyperferritinemia were identified as predictors of development of MODS in our study. The clinical association of severe scrub typhus with raised procalcitonin, hyperferritinemia, and hypoalbuminemia was also established by Peter et al, 31 Kim et al, 32 and Lee et al, 33 respectively. Varghese et al have reported the elevated serum creatinine level as an independent predictor for fatal outcome of scrub typhus patients. 34 A prospective study performed in the adult population showed a significant correlation between severe scrub typhus and following features similar to our study: raised CRP, hypoalbuminemia, and deranged INR. 35
In the present study, anemia, thrombocytopenia, and leukocytosis were seen in 62.9%, 48.4%, and 66.1% cases, respectively. Thrombocytopenia has shown a significant correlation with the development of MODS during illness. The study undertaken by Kumar et al 16 showed similar changes in these parameters. Thrombocytopenia was not associated with an elevated hematocrit, taken as a valuable clue that helps to differentiate scrub typhus from dengue fever. Severe thrombocytopenia was regarded as one of the serious complications in the second week of illness. Another study conducted by Roy et al 36 showed that anemia (78.3%), leukocytosis (56.5%), and thrombocytopenia (17.4%) were important laboratory features. However, neither of them commented on their correlation with disease severity. In the present study, CRP was elevated in 82.3% cases and raised hepatic transaminase was seen in 38.7% patients, but a study conducted by Roy et al 36 showed elevated CRP in 100% cases and transaminitis in 32.6% cases.
We witnessed that the majority had excellent response within 48 hours. The short duration of mechanical ventilation points toward the quick response after doxycycline. We witnessed quite a significant number of scrub typhus cases as septic-shock-like presentation. Progression to MODS puts the burden on morbidity and hospital stay. Sepsis is considered as the most common cause of mortality in ICUs, being fatal in at least 20 to 30% of patients affected. 10 37 38 Unlike other causes of septic shock, with timely detection and intervention these patients showed dramatic response and the outcome has been excellent. Our overall mortality rate was 8%. All the five patients we lost, presented very late (>7 days fever) and had multiorgan failure on admission.
Another recent study 39 conducted in West Bengal, with a smaller cohort, has reported the incidence of MODS in scrub typhus as 53% with a 100% survival rate. A case series 1 reported MODS in one-third of patients (17 out of 50) with dramatic response to timely intervention in nearly all the cases. However, Ratageri et al 40 from South India, who studied 36 children with scrub typhus, reported a bit lower rate of complications and MODS.
This study is one of the largest data analysis of severe scrub typhus infected children requiring PICU admission till date and it will help in stratifying those children requiring more aggressive treatment. However, this is a single-center study. A multicentric study would have warranted a larger population with greater statistical impact. In our study, the scrub typhus patients were diagnosed as probable scrub typhus and confirmation could not be done as facilities for doing a deoxyribonucleic acid-polymerase chain reaction or an indirect immune fluorescence assay were not available at our institution.
Conclusion
Scrub typhus is a significant cause of PICU admission in children in our setting. Infant age group, presence of altered sensorium, reduced urine output, thrombocytopenia, elevated inflammatory markers, coagulopathy, hypoalbuminemia, and hyponatremia warrant risk for MODS. These features shall alert physicians for early referral to an intensive care facility and facilitate early intervention and excellent recovery.
Funding Statement
Funding None.
Footnotes
Conflict of Interest None declared.
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