Myositis tropica

359 ~i'RANSACTIONS OF THE ROYAL SOCIETY OF TROPICAL MEDICINE AND HYGIENE.

Vol. XXXVI. No. 6.

.%Iay,1943.

MYOSiTIS

TROPICA.

B't

J. C. LEEDHAM-GREEN, F.n.c.s., Lt.-Col. R.A.M.C., lion. Assistant Surgeon, North Staffordshire Royal Infirmary, O. i/c Surgical Division Military Hospital AND

WINSTON EVANS,* Capt., R.A.M,C., Pathologist, and Research Fellow in Haematology, Christie Hospital and Holt Radium Institute, Manchester.

This paper describes the clinical features of tropical myositis and adds a note on the pathology. Our observations are based on a series of twenty African patients, natives of Nigeria (eleven cases), the Cameroons (seven cases), and the Gold Coast (two cases), who were admitted with this disease into the Surgical Division of a West African Military Hospital. T h e y constitute approximately 1 per cent. of all African admissions to the hospital. CLINICAL FEATURES. T h e paticnts were admitted with a moderate pyrexia and a tender swelling, diffuse or circumscribed, involving as a rule the musclcs of either the upper or the lower limb. Occasionally two such swellings were present or a second one developed while thc patient was in hospital. These lesions represented either acute abscesses (pyomyositis), or areas of focal necrosis, and in several instances it was difficult to distinguish between the two on clinical grounds. Some unnecessary incisions were made, since even those swellings that exhibited acute tenderness, heat and fluctuation were occasionally found to reveal no * We wish to express our thanks to Col. J. P. J. JENKINS, A.M.S., for permission to publish this communication.

360

MYOSITIS

TROPICA.

TABLE.

Duration

i

Case •Number

of

symptoms (days) . before i admission.

Race.

'Nigeria

I

14

Site of Swelling.

Adductor muscles, left thigh

Cameroons

4

Flexors forearm, right (a)

,, Cameroons :

11

Pectoralis major, left (a) Quadriceps, left

i

I Incision, no pus, biopsy Incision, ! pus, biopsy None Incision, pus

Hamstrings, left

i Nigeria Cameroons i

14

Below left scapula

Nigeria Nigeria Nigeria Nigeria

3 20 3 10

Peroneal region, left Quadriceps, left Quadriccps, left Quadrieeps, right

14 7 2

Anterior abdominal wall Forearm, right Lower left six ribs, posterior (b)

I

Operation.

Incision, no pus ! Incision, pus ~'one

I None None Incision, pus

I0 11 12

13

Gold Coast Gold Coast Nigeria

7

: Cameroons

I 14 15 16

i Cameroons : Nigeria i Nigeria

I

14 2 5

1

17

8

ii C a m e r o o n s i

18

[Nigeria

i

I

19

i Nigeria

I 20

i

I Cameroons i

7

Pectoralis major, left (c) Tensor F. femoris, right Flexors forearm, left Outer side elbow, left Forearm, right Calf muscles, right Quadriceps, right Quadrieeps, right Hamstrings, left Hamstrings, left Scarpa's triangle, left (e) Flexors forearm, right Scapula region, right

None None

Incision, pus None

3 None (d) None None None None

i None I None None

Incision, no pus, biopsy : None .~one

Incision,

no pus Pectoralis major, right

None.

(a) Developed 11 days after admission. (b) Had been struck over the back with a stick 1 week before onset of symptoms. (c) Developed 7 days after admission. (d) Swellings subsided spontaneously and he was discharged from hospital after 14 days. T e n days later he was re-admitted with an abscess in the tensor F. femoris, which was drained. (e) Developed 16 days after admission.

]. c. LEEDIt'AM-GREFNAND WINSTON EVANS.

361

m o r e than a glassy oedemnatous condition of the muscle. T h e regional lymphatic glands were rarely affected. I n those cases that did not proceed to s u p p u r a t i o n the s y m p t o m s might continue for a week or more before abating, and in our experience the administration of sulphapyridine was without effect. S u b s e q u e n t eontractures of the affected muscles were not a feature of the lesion. Case 2 alone showed a slight t e m p o r a r y contracture of the flexors of the middle finger.

Case 18. A typical case. The man, age 25, was admitted to hospital on 19th October, 1942, with a circumscribed tender swelling about 5 by 4 inches, spontaneous in origin and involving the left hamstring muscles in their upper half. Symptoms were of 1 week's duration. Temperature, 101"6° F. Two days later there was no improvement in his condition and he was put on to sulphapyridine by mouth. By 24th October he had received 18 grammes, but the evening temperature was up to 103 ° F. and there was no change in the character of the swelling. Kahn precipitation test was negative, and the white blood cell count was 11,000 per c.mm. Red blood cells showed no sickling in vitro. On 26th October the man was still complaining of great pain and tenderness in the thigh, and an incision was made over the swelling. This revealed nothing but an indefinite oedema of the muscle, a portion of which was excised for histological investigation. Subsequently pyrexia and pain gradually subsided. On 4th November a tender lump developed which involved the muscles in Scarpa's triangle on the left side, but this resolved spontaneously within a few days and gave rise to no constitutional disturbance. I n those cases in which s u p p u r a t i o n had occurred incision revealed an acute abscess cavity containing thick yellowish-white pus from which Staphylococcus aureus was isolated in the few instances in which the pus was cultured.

BIOPSY REPORTS. Case 1. 'File muscle tissue has u n d e r g o n e degenerative changes of tile coagulative type, with complete loss of striations, areas of h a e m o r r h a g e between the muscle fibres and a monocytic infiltration of the inter-fibrillar connective tissue. M u c h fibroblastic reaction is present in completely necrotic areas.

Case 2. T h e r e is m u c h h a e m o r r h a g e into the muscle tissue spaces, accompanied b y a m o n o m l c l e a r cell infiltration. T h e muscle fibres are degenerate and in parts completely necrotic. T h e r e is a s u r r o u n d i n g fibroblastic reaction. Case 18. T h e r e is m u c h degeneration of the voluntary muscle fibres of the coagulative type, the s a r c o l e m m a having completely disappeared and a syncytial mass of necrotic muscle tissue remaining. T h i s is accompanied by areas of h a e m o r rhage into the interstitial tissue, a monocvtic infiltration and s u r r o u n d i n g fibroblastic reaction.

362

MYO~ITIS TROPICA. COMMENTARY.

We consider that tropical myositis is primarily an acute degenerative condition, characterized by haemorrhage into the intermuscular tissue spaces together with a mononuclear cell infiltration, producing an appearance similar to the coagulative necrosis of muscle (Zenker's degeneration), that has been described in typhoid fever, influenza, tetanus, etc. Resolution occurs by fibrosis unless secondary infection intervenes and leads to suppuration (pyomyositis). \Ve have not studied the aetiological factors in detail, but the relationship of the condition to trauma, helminthic infestations, syphilis, yaws and the sickle cell trait appears t.o be very uncertain. In no instance have we observed a collection of the so-called " serous " fluid described by SCOTT (1912), and ~'IANSON-BAHR (1940). REFERENCES. ~[AN,qON-BAHR,P. (1940). :Vlanson's Tropical Diseases, p.'705, 1lth ed. London : Cassell & Co. SCOTT, H.H. (1912). J. trop. ZF[ed.ltyg., t5, 97.