Worsening Muscle Weakness in Myasthenia Gravis Patient Suffering Dengue Infection Hardjo Lugito NP 1* , Margaret 2 , Andree Kurniawan 1 and Merlyn Tjiang 1 1 Internal Medicine Department, Faculty of Medicine, Pelita Harapan University, Indonesia 2 Siloam Karawaci General Hospital, Indonesia * Corresponding author: Nata Pratama Hardjo Lugito, Internal Medicine Department, Faculty of Medicine, Pelita Harapan University, Indonesia, Tel: 622154210130; E- mail: nata_pratama_hl@yahoo.com, nata.lugito@uph.edu Rec date: Apr 10, 2014; Acc date: May 24, 2014; Pub date: May 27, 2014 Copyright: © 2014 Hardjo Lugito NP, et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Abstract The dengue infection is the second most common mosquito-borne disease affecting human beings. Dengue can manifest with a wide range of neurological features, which have been noted - depending on the clinical setting in 0.5-21% of patients with dengue admitted to hospital. Neuromuscular complication can manifest in muscle weakness, which can be found in forms of myalgia, myositis to rhabdomyolysis, Guillain – Barre syndrome and hypokalemia. The pathogenesis and also the role of host and virus in dengue neuromuscular complications were not clear. In this case report, a 36 year-old female MG patient suffered from dengue infection. The MG symptoms worsen and then improved along with the course of dengue. There was a possibility that muscle weakness in this patient were related to dengue disease as the symptoms improved along with the resolving dengue, but the mechanism could be associated with virus neurotropic effect, systemic infection effect or immune mediated. Keywords: Dengue; Myasthenia gravis; Muscle weakness Introduction Dengue is a mosquito-borne viral disease caused by one of four closely related Dengue Virus (DENV) serotypes. It is the second most common mosquito-borne disease affecting human beings after malaria. Around 4 billion people are at risk of the disease, with about 100 million cases of symptomatic dengue occurring annually [1]. In United Kingdom, the prevalene of Myasthenia Gravis (MG) is 15 per 100,000 population [2]. Since the end of the 1990s, evidence of DENV neurotropism has increased [3,4]. Dengue infection can cause neuromuscular complication which can manifest as muscle weakness. Muscle weakness can be found in forms of myalgia, myositis to rhabdomyolysis [5], Guillain-Barre syndrome [6,7] and hypokalemia [8,9]. Pathogenesis of neuromuscular complications and role of host and virus are not clear, and might be associated with virus neurotropic effect, systemic infection effect or immune mediated such as in Guillain – Barre syndrome in dengue infection. In MG, an autoimmune disease affecting the neuromuscular junction, anti – acetylcholine receptor (AChR) antibodies caused lysis – mediated by complement, cross – link, decreased production and direct agonist inhibition of AChR [9]. In this case report, a 36 year-old female MG patient, whose symptoms worsen when she suffered from dengue infection. The MG symptoms improved along with resolving dengue infection. There was a possibility that muscle weakness in this patient were related to dengue disease as the symptoms improved along with the resolving dengue, but the mechanism was not clear. Case Illustration Female, 36 year-old was admitted with fever since 4 days prior. The fever was continuously high with no chill. She also complained of arthralgia, headache and extremity muscle weakness. There was no epistaxis or gum bleeding. She complained of difficulty in swallowing food and liquid, difficulty to open eyelids and increasing difficulty to breathe since prior 2 weeks. She did not have history of asthma. Neurological examination found extremity motor strength of 4444 on four extremities, decreased physiological reflexes, 5th and 10th cranial nerve palsy, and ptosis. She had experienced same complains 8 month ago when she was diagnosed of MG. Her chest computed tomography scan then was normal. She was on pyridostigmine 60 mg three times daily since 8 month ago. Her laboratory examination revealed thrombocytopenia (93,000 /μL), positive dengue IgG and IgM using Panbio ® Dengue IgG IgM Capture ELISA. She received fluid therapy and pyridostigmine 60 mg four times daily. Her complains (ptosis, cranial nerves palsy and extremity motor strength) and laboratory improved, then she was discharged on the 6th day of admission. Discussion MG is an acquired autoimmune disease affecting the neuromuscular junction, especially the nicotinic AChR which located on the post synaptic endplate membrane. Acetylcholine produced and released normally, but the post synaptic effect decreased due to decreased AChR, which its membrane is occupied by antibodies and complement. Anti-AChR antibodies causing the decreased AChR by lysis-mediated by complement, cross-link, decreased production and direct agonist inhibition [9] (Table 1). Journal of Tropical Diseases & Public Health Hardjo Lugito, et al., J Trop Dis 2014, 2:3 http://dx.doi.org/10.4172/2329-891X.1000140 Case Report Open Access J Trop Dis ISSN:2329-891X JTD, an open access journal Volume 2 • Issue 3 • 1000140