Thorax: first published as 10.1136/thx.25.6.748 on 1 November 1970. Downloaded from Tlhorax (1970), 25, 748. Arthritis and arthralgia in infection with Mycoplasma pneumoniae M. C. JONES Brompton Hospital, London, S.W.3 Joint involvement following infection with Mycoplasma pneumoniae is extreinely uncommon. Four patients are presented in whom joint symptoms occurred, giving rise to diagnostic difficulties in three. It is suggested that these manifestations were due to M. pneumoniae. Mycoplasma pneumoniae, first identified as the were painful on movement but otherwise appeared cause of Eaton agent pneumonia in 1962 by normal. The chest was clear. Chanock, Hayflick, and Barile, remains the only Investigations Haemoglobin 12-6 g./100 ml., WBC species of mycoplasma proven to be a human 6,200/cu. mm., ESR 37 mm. (Westergren). Sputum pathogen (Griffin and Crawford, 1969). It attacks sterile on culture; blood cultures negative; antistrepto- mainly the respiratory system but is also a recog- lysin 0 (ASO) titre less than 200 units/ml. A chest nized cause of acute haemolytic anaemia (Peterson, radiograph showed consolidation involving the anterior Ham, and Finland, 1943) and erythema multi- segment of the left upper lobe. Initial complement forme (Gordon and Lyell, 1969). Involvement of fixation test (CFT) to M. pneumoniae showed a titre the ear, heart and central nervous system has also of less than 1 in 5 together with a cold agglutinincopyright. been described (Lambert, 1 968a), and recently titre (CAT) of I in 16 at 4° C. involvement Treatment with ampicillin was ineffective, the tem- three cases with joint have been perature remaining at 102' F. After four days tetra- reported (Lambert, 1968b). A further four cases cycline was started, the temperature returned to are now presented. normal within 48 hours, and the pneumonia resolved radio&ogically within four weeks. Cultures of the http://thorax.bmj.com/ sputum yielded M. pneumoniae after two weeks' CASE REPORTS incubation, when the CFT had risen to 1 in 320. The patient made a good clinical recovery but continued CASE I (Table) A girl of 14 years presented with to complain of pain and stiffness in both knees and fever, malaise, headache and sore throat. She was had difficulty in walking for three months. treated with penicillin but remained unwell. Five weeks later she developed pleurisy with pain and CASE 2 (Table) A woman aged 62 years, a mild stiffness in both knees: a week later she became chronic bronchitic, was admitted to hospital with a increasingly ill with severe headache, rigors, fever 10-day history of fever, malaise, headache and pro- rising to 105° F. and mucopurulent sputum. On exam- ductive cough. The symptoms had failed to respond on September 24, 2021 by guest. Protected ination there was evid2nce of tonsillitis. Both knees to either lincomycin or tetracycline. On examination B L E Cnmnlfxmfnt Fivqtinn Tp,-ctz Cold Agglutinin Test ASO Case Sex Age Affected Joints 11mp 1ernem Titre 1st 2nd Ist 2nd L I F 14 Kneees <5 > 3201 16 <200 2 F 62 Shou Iders, elbows, knees, hainds 80 320 <10 160 3 M 32 Wrisits, elbows, shoulders, knlees, ankles 128 64 250 4 M 15 Elbows, knees, ankles 1,280 2,560 > 1,280 160 800 ~I- 17 Kneees, ankle 1,280 90 - - 200 L2 M I I Kneee, ankle 80 1,280 512 - 100 L3 M 14 Han(ds, shoulders, knees, feeet 320 20 32 - 230 :~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 'M. pneumoniae isolated from sputum. Table also includ2s cases LI-3 taken from Lambert (1968b). All cases except 3 had pneumonia. 748 Thorax: first published as 10.1136/thx.25.6.748 on 1 November 1970. Downloaded from Mycoplasma pneumoniae 749 she was ill, drowsy and dehydrated with a temperature diagnostic level of 1 in 128 on admission to I in 64 of 102-6° F. Apart from bilateral crepitations in the nine days later, indicating that the infection was chest there were no other abnormal findings. recent. He continued to complain of pain in the right wrist and phalangeal joints for some weeks but he Investigations Haemoglobin 12-7 g./100 ml., WBC has remained well for over two years. 12,000/cu. mm., ESR 120 mm. (Westergren). Sputum culture negative. A chest radiograph showed bilateral CASE 4 (Table) A boy aged 15 years developed a bronchopneumonia, confluent in the right upper lobe. sore throat which was treated with oral penicillin. He Next day she complained of pain and stiffness in was admitted to hospital two weeks later complaining the elbows, shoulders and knees followed by painful of painful, tender, swollen ankles and knees. On swelling of the phalangeal joints of both hands. Three examination he had a temperature of 101° F.; there days later her haemoglobin had fallen to 8-2 g./100 were bilateral effusions of both knees and ankles with ml. and showed evidence of auto-agglutination in that erythema around both elbows. The pulse rate was cold haemagglutination was present. The reticulocyte 80/minute with sinus rhythm. No other abnormal count (5%), serum bilirubin (09 mg.%) and trans- physical signs were noted. aminases (SGOT 65 i.u., SGPT 47 i.u.-normal 0-40 Investigations Haemoglobin 14 2 g./100 ml., WBC i.u.) were elevated whilst her CAT rose from less than 8,000/cu. mm., ESR 106 mm. (Westergren). Throat 1 in 10 to 1 in 160 in 8 days. Initial CFT to swab cultures negative; blood cultures negative; mid- M. pneumoniae was 1 in 80: the sheep cell stream urine cultures negative; Paul-Bunnell nega- differential agglutination test (DAT) and Latex tests tive; ASO titre 800 units/ml., chest radiograph within were both negative. normal limits. Though her temperature returned to normal on the An initial diagnosis of acute rheumatic fever was fifth day whilst still on tetracycline, her general con- made and penicillin and salicylates were started. dition remained poor and a chest radiograph showed During the following week his condition remained extension of the consolidation in the right lung. By unchanged; there was no tachycardia and serial the ninth day her CFT had risen to 1 in 320. In the electrocardiograms were normal. His condition then following two weeks she made a slow recovery and worsened, the temperature rising to 1020 F. A repeat was discharged home continuing to complain of pain showed consolidation in the chest radiograph posterior copyright. and stiffness in the joints, particularly in the right segment of the left lower lobe. Ampicillin was sub- shoulder. The radiological changes resolved within stituted for penicillin without benefit. Three days later four weeks and her ESR on discharge was 29 mm. the CFT to M. pneumoniae was reported as greater (Westergren). Five months later the CFT had fallen than 1 in 1,280 whilst the CAT was 1 in 1,280. After to 1: 20, and she still had some discomfort in the ampicillin had been replaced by tetracycline the tem- right shoulder and knee. perature fell to normal within 24 hours, the patient making a rapid uneventful recovery. Two weeks later http://thorax.bmj.com/ CASE 3 (Table) A man aged 32 years was admitted the CFT was 1 in 2,560 and the CAT I in 160. Sali- to hospital with a five weeks' history of pain, stiffness cylates were then discontinued. One month after and swelling of both knees spreading over the next treatment had finished the ASO titre was normal. He four weeks to involve the shoulders, elbows, ankles has remained perfectly well for over two years. and wrists. He then developed a sore throat followed by an itchy erythematous rash over the back, abdomen, DISCUSSION and legs; he had not received any drug treatment. On examination he was afebrile though flushed and The four cases presented here are taken from a with injected fauces. The left wrist was slightly personally collected series of 110 cases of infection swollen because of a joint effusion and there was a with M. pneumoniae. Either the lack of awareness on September 24, 2021 by guest. Protected subcutaneous nodule over the extensor aspect of the characteristic elbow. There were no signs in the previously affected of the disease or the absence of any joints other than some residual tenderness. There were clinical features often meant that early serological no other abnormal findings. Pulse rate was 100/ tests were omitted whilst cold agglutinins which minute. might have allowed a tentative diagnosis to be made earlier in the illness were rarely looked for. Inivestigations Haemoglobin 14 3 g./100 ml., WBC Undoubtedly a major problem in early diagnosis 9,600/cu. mm., ESR 53 mm. (Westergren); throat was the unavoidable delay in obtaining positive swab culture negative; chest radiograph was within serological evidence of infection. That the diag- normal limits; serial electrocardiograms were normal; nosis was only established after recovery mattered ASO titre 250 units/ml. that as a result A tentative diagnosis of acute rheumatic fever was little in most instances except made and he was treated with intramuscular followed treatment was haphazard: 13 patients were treated by oral penicillin. The rash disappeared in a few days effectively with tetracycline, and a further 19 were and the nodule regressed completely over three weeks. given tetracycline later in the illness after a variety The CFT to M. pneumoniae showed a fall from the of other antibiotics had proved useless. Thorax: first published as 10.1136/thx.25.6.748 on 1 November 1970. Downloaded from 750 M. C. Jones Additional diagnostic difficulties arose in these The diverse manifestations of infection with four patients whose illness needed to be distin- M. pneumoniae resemble quite closely those pro- guished from other causes of arthralgia, notably duced by other mycoplasma species in a wide rheumatic fever and rheumatoid arthritis.