We reviewed case records of 40 in-patients (22 boys) with serologically confirmed dengue fever between 1st October and 30th November, 2013. Severe dengue was seen in 30, out of which 12 (30%) had compensated shock. Splenomegaly (6,15%) and encephalopathy (4,10%) were the commonest atypical features. Atypical manifestations of dengue fever were more common than that reported in the past.

Keywords: Dengue, Encephalopathy, Myositis, Splenomegaly.

The clinical presentation of dengue fever has a wide spectrum; atypical manifestations have also been reported [1,2]. In this communication, we describe the atypical manifestations in pediatric inpatients with serologically confirmed dengue virus infection.

After necessary permissions, case records of all children admitted at our department, between 1st October and 30th November, 2013 with serologically confirmed dengue were screened. Case-records of patients leaving the hospital within 24 hours of admission, and those with inadequate information were excluded. Data were entered in a structured proforma.

At our department, dengue virus infection is confirmed as positivity for NS 1 antigen detection and IgM Rapid test / IgM ELISA. Classification of patients is done according to WHO 2009 criteria [3]. Liver and renal function tests are done at baseline in all patients. Patients with altered liver enzymes undergo ultrasound abdomen. Coagulation studies are done in those with features suggestive of disseminated intravascular congulopoly. Investigations are done to rule out co-infections in those with suggestive features. Additional investigations are done as per clinical course. Further management is guided by clinical features and investigations, as per standard guidelines [3].

During the period of study, 48 children with confirmed dengue fever were admitted but data of 8 were excluded (2 left against medical advice within 24 hours, 1 absconded, 1 case-sheet was not traceable and 4 had incomplete documentation). Out of 40 included chidren, 22 were boys, and the median (range) age was 5.9 (4-13.25) years. Atypical manifestations were seen in 16 (40%) patients; splenomegaly (15%) and neurological abnormalities (10%) were the most common. Acute respiratory distress syndrome (ARDS) and disseminated intravascular coagulation (DIC) were seen in two children each, and one child had diarrhea and myositis, each. Neurological abnormalities were present in four children (10%), two of whom died. CSF examination was normal in two and showed hypoglycorrhachea without pleocytosis in two patients. Magnetic-resonance-imaging of head was normal in one child; it was not done in other three. Ultrasonography of abdomen was done in 16 children, and it was abnormal in 8 (6, hypoechoic hepatic parenchyma with ascites; 2, peri-gall bladder edema with wall thickening, 1 having cholelithiasis in addition).

Splenomegaly occurred commonly probably because the Dengue virus antigen is found predominantly in lymphoreticular cells. In two previous studies, splenomegaly was reported in 13% and 32.4%, respectively [4], but a much higher incidence of 60% was reported in a study conducted in Lucknow [5].

Though varying degrees of myalgias are commonly seen; muscle weakness, as seen in this study, is an uncommon manifestation. There are two suggested mechanisms viz., direct invasion of the muscle fibers or release of myotoxic cytokines, particularly tumor necrosis factor (TNF), injuring the affected muscle [10].

Despite a small sample-size and retrospective study design, we found atypical manifestations of dengue fever to be more common than reported, especially encephalopathy. Practitioners need to be aware of the same to ensure prompt recognition and early management.

Contributors: AP: conceived the idea, reviewed the records and analyzed the data; DM: planned the study and helped in manuscript preparation; MJ and JM: important intellectual inputs in the planning and conduct of the study, and manuscript preparation. All the authors were involved in the final approval of manuscript.

Funding: None; Competing interests: None stated.

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