By Major M. P. Vora, I.M.S. (Retd)

Indian Medical Record

A monthly journal of Public Health, Tropical Medicine and Surgery etc .

Volume LXXXV, Number 2, of February 1965

Pages 13-15


This article was solely contributed to Indian Medical Record


Chancroid is an autoinoculable infection due to Haemophilus ducreyi and characterized by painful genital ulceration, often followed by unilateral and unilocular suppurative regional lymphadenopathy. It is usually contracted through sex relations and world-wide distribution. Clinically, it gives rise to painful ulcer or ulcers at the site of inoculation of the germs. Being of venereal origin, the lesion is on the genitalia. The incubation period is short i.e. 1 to 3 days. Initially, the lesion is a small crack or an abrasion or an ulcer. In the course of time, the lesion increases in size, becomes somewhat irregular in outline, its base remains soft and covered with purulent exudates, and the borders are soft, irregular and undermined with red periphery. It is often called ‘soft sore’ because of the lack of infiltration and induration, which are conspicuous in a chancre. It is often painful and presents multiple lesions on account of its autoinoculable nature.


Haemophilus ducreyi bacillus has a special predilection for the skin. In the male, the lesion is found on the prepuce or the frenum. At times it may be intra-urethral. Secondary phimosis is not uncommon. In the female, the lesion may appear on the labia, fourchette, or the clitoris. Involvement of the anus by direct extension is common in women.


The clinical varieties of chancroid are:-


(1) small uncomplicated ulcer - usually met in persons of clean habits,


(2) papular or crusted ulcer often associated with warty growths – usually seen in women, and


(3) phagedenic rapidly destructive ulcer often seen among the unhygienic and underprivileged.

Inguinal adenitis, which develops in about 5 to 10 days after the appearance of the chancroid, is a common feature especially in persons with unclean habits. It is usually unilateral and produces unilocular, soft fluctuation bubo. This complication can be prevented. Advising rest in bed, frequent dry heat applications to the groin, promoting good drainage of discharges, and administration of sulpha drug, early in the course of disease, are sure to prevent adenitis and bubo formation. In absence of these measures, inguinal lymph nodes become enlarged, tender and painful and overlying skin becomes red. In a few days, the glands become soft and fluctuating, the skin on them becomes thin, shriveled and bursts with an opening. A good amount of pus is discharged. Unilocular suppuration is very characteristic. Systemic changes are very mild or absent. The most important symptom in chancroid is pain both at the ulcer and in the lymph glands involved. The skin over the glands does not become thickened, oedematous and grooved as in case of adenopathy in lymphgranuloma venerum, which ca be palpated with ease and without discomfort or pain.


Chancroid may be contracted with other venereal diseases, such as syphilis, gonorrhoea etc. It should always be suspected clinically whenever there is a painful purulent ulcer of short incubation period, with an acute and painful lymphadenopathy. However, diagnosis must not be made on clinical impressions alone. It must be confirmed by laboratory tests.


It would not be right to call a genital ulcer chancroid simply because the dark field microscopy for Tr. pallidum is negative. It is equally important to exclude other venereal diseases and to demonstrate H.ducreyi in the smears taken from the ulcer. A smear showing H.ducreyi is diagnostic.


The lesion is thoroughly cleaned with normal saline and a smear is made with a short, thick platinum wire on a clean slide, from the undermined or advancing border of the ulcer. The slide is hen dried, fixed by heat and stained with Unna-Peppenheim or Giemsa stain. Ducreyi bacillus is Gram-negative, short, and thick with rounded ends which often stain deeply to give “safety-pin” appearance. It may be intra or extra cellular. The smears from advancing borders show parallel rows of bacilli suggesting “shoals of fish”. Chancroid in the first week of its appearance is usually full of bacilli. The importance of repeated negative dark-field microscopy for Tr. pallidum and serologic test for syphilis to eliminate the possibility of syphilis, cannot be overstressed for about 25% cases have a double infection.


Ito-Reensteirna Test or Ducrey Vaccine Test:-


Ducrey vaccine (Lederle Laboratories) 0.1 cc is injected intradermally on the flexor aspect of the forearm. If an erythematous papule 7 to 12 mm in diameter develops at the site of infection, within 24 to 48 hours, the test is considered positive and indicates that the patient is infected with H.ducreyi. the interpretation is conclusive only if the patient has never suffered from venereal disease previously. The test is positive in the second week of infection or after the involvement of lymph nodes. A minimal reaction which fades away rapidly is considered negative.


Culture of H.ducreyi and microscopic examination of the tissue are additional methods of diagnosis.


Differential Diagnosis:-


Diagnosis for chancroid depends on exclusion of other ulcerative lesions on the genitalia and demonstration of H.ducreyi in the smear taken from the lesion. It can never be done correctly on clinical examination alone. Short incubation period, painful ulcer, unilocular suppurative adenopathy, mild systemic manifestations and negative dark-field microscopy for Tr. pallidum are suggestive. Other ulcerative lesions – chancre, herpes genitalis, traumatic-coccogenous streptococcal tubercular-seborrhoec-monilial-scabetic ulcer, secondary syphilitic lesion, primary lesion of L.V., venereal warts, molluscum contigiosa, psoriasis, lichen planus, lupus vulgaris, urticaria, lupus erythematosus, chicken-pox, small-pox, pediculosis pubis, granuloma inguinale, and epithelioma, are lesions which are seen on the genitalia and need to be differentiated.




Chancroid can be prevented if timely precautions are taken. A thorough wash with soap and water and then an antiseptic lotion immediately after the contact is sure to prevent infection. Sulpha drug in sufficient amount orally just before and after the contact for a few days, has been used successfully.


Local Treatment:-


With the advent of sulpha drugs, the importance of local treatment of chancroid has become of minor importance. Normal saline cleaning and promotion of drainage is all that is ordinarily required. Hypertonic saline is advised if oedema is present. If there is phimosis, dorsal slit or circumcision may have to be considered. In case operative procedure is objected, warm subpreputial irrigation two or three times a day, are suggested. If the nodes are tender, rest in bed, dry heat applications and sulpha drug orally one Gm, four or five times a day is advised. If there is softening and fluctuation, the bubo must not be incised. It should always be aspirated with 18 gauze needle. At times, this has to be repeated once or twice. A few injections of chancroid vaccine or T.A.B. vaccine intravenously at two day intervals, in increasing dosage, will help to bring down about early resolution.


Systemic Treatment:-


Most cases of chancroid can be treated in the out-patient; those with extensive ulceration, phagedena or buboes need hospitalization. Administration of sulpha drug is the therapy of choice and results are uniformly good. Both sulphadiazine and sulphathiazole are equally effective. The average dose of one Gm, at 4 hourly intervals, four or five times, a day, for five to seven days, depending on the severity of the condition, is suggested. Penicillin is not at all effective and not recommended in chancroid. On the contrary, it is likely to mask co-existing early syphilis or alter its normal course.


Complicated cases:-


If chancroid and gonorrhoea or L.V. are present, they can be treated with sulpha drugs. If chancroid and early syphilis are present, penicillin-G I.M., 6m.u. in 10 days plus sulpha drug orally for 5 to 10 days, should be started simultaneously.




After the treatment, every patient should be kept under observation for a period of 3 to 4 months, during which periodic physical examination and serologic test for syphilis, should be carried out. Complicated cases need additional check-ups to confirm cure of infection as the case may be.