Background Dengue is one of the common arboviral infections and is a public health problem in South East Asia. The aim of this systematic review and meta-analysis was to evaluate the prevalence and distribution of dengue in SAARC (South Asian Association for Regional Cooperation) countries. Methods The PubMed, PubMed Central, Embase and Scopus databases were searched for relevant studies. Statistical analysis on data extracted from the selected studied was conducted using the Comprehensive Meta-Analysis Software (CMA) version 3 software package. Proportions were used to estimate the outcome with a 95% confidence interval (CI). Results Across all studies, among cases of suspected dengue, 30.7% were confirmed dengue cases (proportion: 0.307, 95% CI: 0.277–0.339). The seroprevalence of dengue immunoglobulin (Ig)G, IgM or both (IgM and IgG) antibodies and dengue NS1 antigen was 34.6, 34.2, 29.0 and 24.1%, respectively. Among the different strains of dengue, dengue virus (DENV) strains DENV-1, DENV-2, DENV-3 and DENV-4 accounted for 21.8, 41.2, 14.7 and 6.3% of cases, respectively. The prevalence of dengue fever, dengue hemorrhagic fever and dengue shock syndrome was 80.5, 18.2 and 1.5%, respectively. Fever was a commonly reported symptom, and thrombocytopenia was present in 44.7% of cases. Mortality was reported in 1.9% of dengue cases. Conclusions Dengue is a common health problem in South East Asia with high seroprevalence. DENV-2 was found to be the most common strain causing infection, and most dengue cases were dengue fever. In addition, thrombocytopenia was reported in almost half of the dengue cases. Graphical Abstract

Methemoglobinemia is a rare condition characterised by hypoxic state manifesting as headache, nausea, fatigue, and confusion. We report a 2-year-old boy presenting with fever and cough for 7 days with an episode of hypoxia as the saturation declined and did not improve on face mask oxygenation. On further evaluation, acute intravascular hemolysis was established following decreased haemoglobin level, increased levels of lactate dehydrogenase, and unconjugated bilirubin in the setting of documented infection. Assessment of arterial blood gas showed a significantly raised saturation gap and detection of methemoglobin confirmed the diagnosis. He was managed conservatively with packed red blood cells transfusion following which hypoxia was corrected. Methemoglobinemia as a result of hemolysis can be a non-cardio-respiratory cause of hypoxia and inciting aetiology needs to be addressed.

Introduction: Kawasaki disease (KD) is the most common cause of childhood vasculitis affecting small- and medium-sized arteries. The cause of this disease is unknown with an overall prevalence of 0.10% making this a rare entity. Case presentation: Here the authors present an index case of a 2-year-old child presenting with a persistent high-grade fever of more than 5 days and a 3-day history of bilateral swelling of hands and feet along with cervical lymphadenopathy. On the subsequent day of admission, the child developed mucocutaneous symptoms and cervical lymphadenopathy. The diagnosis of KD was made, and it was successfully treated with intravenous immunoglobulin and aspirin. Clinical discussion: Timely diagnosis and early treatment of KD are challenging due to the lack of definitive diagnostic tests. Watchful waiting for symptoms may be necessary before a diagnosis can be made because not all clinical symptoms are present simultaneously as in the index case. Conclusions: This case highlights considering KD as a differential diagnosis of nonresolving fever in children with mucocutaneous findings. Intravenous immunoglobulin along with aspirin is the mainstay of therapy and should be started as early as possible to prevent detrimental cardiac complications. There is a high tendency of diagnostic dilemmas due to a wide array of nonspecific presentations thus healthcare providers must be more vigilant of this entity.

Osteitis fibrosa cystica or brown tumor is a rare skeletal manifestation of hyperparathyroidism. Awareness of this condition is imperative to making a correct diagnosis. We present a case with multiple pathological fractures who had undergone extensive workup for malignancy before reaching the definitive diagnosis of primary hyperparathyroidism.