Scrub typhus: another treatable neurological infection

Infectious diseases of the nervous system are an evolving and extremely interesting area of neurology. There always seems to be a new infection on the horizon and this means that neurologists constantly need to stay up-to-date on how these infections present clinically. Importantly, many are treatable and this means that you have to be on the ball to ensure that patients can receive early treatment with a reduction in long-term disability.

In this issue of JNNP, Misra et al from Lucknow in India have presented a comprehensive analysis of patients admitted to their institution in 2012-2013 who had been diagnosed with Scrub Typhus, a condition transmitted by a rickettsial organism that is usually spread by ticks, lice and fleas http://jnnp.bmj.com/content/86/7/761.abstract. There are certain areas of the world where this organism is endemic, including India, Pakistan, Russia, Japan and Australia.

Amazingly, the authors identified 38 cases in this short period of time and have provided a wonderful overview of how these patients present. Meningitis and encephalitis are common presentations with patients often experiencing headache, fever and disorientation. The condition can also be life-threatening and some patients in this series were admitted to intensive care units with lung involvement or kidney failure. The most important aspect of this paper is that ~90% had a good response to antibiotic treatment with doxycycline. As suggested by the authors, scrub typhus should be included in a list of conditions that can cause encephalopathy with fever, particularly in patients who live in or who have travelled to areas where this condition is endemic.