A seven-year-old boy admitted with the complaints of fever, weakness in legs, sensory loss in lower limb, and difficulty in voiding lasting for two weeks. His initial symptoms also included cough and fever. His spinal magnetic resonance imaging scan demonstrated acute transverse myelitis, and Mycoplasma pneumoniae-specific IgM and IgG antibodies were found to be positive in cerebrospinal fluid (CSF) and serum samples. He was treated with a single high-dose intravenous immunoglobulin (2 g/kg/dose) and clarithromycin.

Mycoplasma pneumoniae is a frequent cause of upper and lower respiratory tract infections in children. Central nervous system (CNS) manifestations are among the most frequent extrapulmonary complications during the course of the disease. They occur most frequently in children, usually within three weeks after the onset of respiratory illness, with an incidence of approximately 1 in 1,000 patients.

In this report, we present a seven-year-old boy with transverse myelitis during the course of Mycoplasma pneumoniae infection with serological confirmation both in serum and CSF samples.

The most serious nervous system complications of M. pneumoniae infections are acute transverse myelitis and acute disseminated encephalomyelitis[4,5]. Pathogenesis of central nervous system (CNS) disease caused by M. pneumoniae is incompletely understood but autoimmune phenomena seem to have a major role in the development of myelitis[6].

Acute transverse myelitis is characterized by motor, sensory and autonomic dysfunction due to demyelinization of the spinal cord and neuronal damage following focal inflammation. Parainfectious causes account for 30-60% of the cases. Differential diagnosis includes vascular, infectious, neoplastic, autoimmune, collagen vascular and demyelinating conditions. An idiopathic group has also been defined since they are not related to any systemic diseases and etiology could not be defined.

We report our experience in a seven-year-old boy with acute transverse myelitis due to Mycoplasma pneumoniae infection, with rapid improvement after macrolide therapy.

In the majority of the patients who have M. pneumoniae-associated transverse myelitis, respiratory system infection develops around 10 days prior to neurological findings[9]. However, it has been shown in various studies that this period may vary from 1 day to 30 days. Clinical findings may range from non-specific upper respiratory tract infections to pneumonia[10]. Likewise, our patient had respiratory system findings such as cough 12 days before presentation to our hospital.

Serological methods are used frequently for the diagnosis of M. pneumoniae. Yet, there are patients with negative serology even if positivity is demonstrated with polymerase chain reaction[11]. As in our case, there are a few patients reported in the literature who have positive antibodies along with positive antibodies in CSF[12].

For the diagnosis of transverse myelitis, MR imaging is one of the most reliable methods. MR imaging findings correlate with the development, grading and the prognosis of the disease[13]. Nevertheless, it should be kept in mind that MR imaging is not so helpful in differentiation of the many causes of inflammatory myelopathy[14].

The role of antibiotic therapy in the treatment of M. pneumoniae-associated myelitis remains undefined because of unsatisfactory knowledge regarding the pathogenesis and natural history of the disease and of controlled trials assessing such therapy. Antibiotic therapy has been temporally associated with clinical improvement in some cases of M. pneumoniaeassociated acute transverse myelitis[11]. It should be kept in mind that some patients could improve completely and spontaneously without antibiotics[15]. Although macrolides are regarded as first choice in M. pneumoniae infections, the fact that they can not penetrate the blood brain barrier is an important disadvantage of these drugs. Azithromycin, which can pass the blood brain barrier, is an agent that should be preferred in children younger than eight years old and ciprofloxacin in adults[6]. In addition, although immune modulators such as steroids[7,6,17], azathioprine, IVIG[12] and plasma exchange[7,16] were used in treatment, their role still remains to be defined.

Although it was not clear whether or not rapid improvement of our patient was associated with antimicrobial treatment, we suggest anti-microbial therapy in cases with suspected mycoplasma infections associated with transverse myelitis. In conclusion, M. pneumoniae should be considered in the differential diagnosis of patients who have CNS findings associated with fever and cough and should be investigated with serological, molecular and culture methods.