Subungual Erythema in Lymph Node Tuberculosis withErythema Nodosum

AK Janmeja, PR Mohapatra, Rominder Kaur

Case Report
We encountered a case of tuberculous lymphadenitis with erythema nodosum presenting with an unusualmanifestation as subungual erythema in all the digits. Relevant literature and the possible explanation forthe subungual erythema have been discussed. ©


Various kinds of tuberculo-protein hypersensitivityphenomena are encountered in tuberculosispatients either in association or in isolation of the activedisease e.g. erythema nodosum, phlyctenularconjunctivitis, reactive polyarthritis, increased dermaltuberculin hypersensitivity, pleural effusion, pericardialeffusion etc. However, co-existence of many of themtogether in one patient is very unusual. The present caseelicited at least four such hypersensitivity phenomenanamely erythema nodosum, reactive polyarthritisphlyctenular conjunctivitis and highly reactivetuberculin test in addition to a unique subungualerythema. All tuberculo-protein hypersensitivityphenomena are known to be reversible and subsideeither spontaneously or on taking specific treatment fortuberculosis.


A 16 years young girl presented with 2 months historyof progressive painful swelling of around 2.5 centimeterdiameter on left side of the neck, followed by low gradefever and reddish in coloration of fingernails in all digits.Nearly 20 days prior to the presentation she developedpainful skin nodules over the front of right ankle andover both shins along with moderate pain in knees,ankles, elbows and wrist sparing distal smaller joints.For the same duration she had been having mild painand itching in both eyes but without any discharge. Nopast history of diabetes mellitus, tuberculosis or jointpain could be elicited. Her family history wasunremarkable.

Patient was moderately built and nourished withnormal vital signs. Her eyes revealed redness in lateralscleral regions on either side. Detailed ophthalmologicexamination revealed phlyctenular conjunctivitis in botheyes with normal fundus and anterior segments. Atender, soft, non-fluctuating and mobile cervical lymphnode of 2.5 X 2.5 cm in size was seen just posterior to themiddle third of sternocleidomastoid muscle on left side.Her both hands revealed subungual erythema in all thedigits. The erythema extended to distal two-thirds of thenail bed and was well demarcated from the proximalposition with incomplete involvement of lunula (Fig.1)The tenderness was also positive in all phalanges.Multiple painful reddish-blue skin nodules of 5-15mmsize were observed over the shins and entire abdominalwall. The examination of respiratory, cardiovascular andcentral nervous was essentially normal. The knee, elbow,wrist, and ankle joints on either side were tender andwere painful on movement; however, only knee jointswere minimally swollen.

Complete hemogram and routine serum biochemistrywere normal. Rheumatoid factor, LE (lupuserythematosis) cell phenomenon and CRP (C- reactiveproteins) were negative. Blood culture was sterile andWidal test was negative. The erythrocytes sedimentationrate (ESR) was 47mm 1st hour by Mantoux test after 48hours was highly positive with vesicle formation (Fig.2).Radiographs of chest, knees, elbows and ankle jointswere normal. Abdominal ultrasonography revealednormal study. Fine needle aspiration cytology (FNAC)of the enlarged lymph node was suggestive oftuberculosis and stained positive for acid-fast bacilli(AFB). The shin nodule biopsy was compatible with thatof erythema nodosum. Consequently, the diagnosis ofcervical lymph node tuberculosis with erythemanodosum with phlyctenular conjunctivitis withsubungual erythema was made.

The patient was started on tuberculosis chemotherapy in the form of; isoniazid, rifampicin,pyrazinamide and ethambutol daily. The erythemanodosum, phlyctenular conjunctivitis and otherconstitutional symptoms disappeared with in 2-3 weeks.The subungual erythematous spots gradually fainted topurple, then brownish and ultimately disappearedcompletely within 3 weeks. By 2 months, the patientbecame asymptomatic and lymph node regressed.Patient was changed on to continuation phase of i.e.isoniazid plus rifampicin for a period of 4 months,which was completed uneventfully.


In India erythema nodosum is the commonestpaniculitis and nearly 70% are idiopathic.1 It has beenreported to accompany primary tuberculous infectionin 1-2% of British2 and 5-15% of Scandinavian cases. 3 Itis rare below the age of 7, with an increase in frequencyup to puberty. It is common after puberty and 80-90%cases are females.3 Tuberculin conversion is said toprecede the eruption by a few days to a few weeks inmost cases, although erythema nodosum may also occur later in primary or even post primary tuberculosis. Therash is probably a manifestation of the Arthusphenomenon, as in erythema nodosum leprosum, wherelocal deposits of immunoglobulins, complements andsoluble mycobacterial antigens have been demonstrated.4The characteristic feature of erythema nodosum is thepresence of tender, dusky red, slightly nodular lesionson the anterior surfaces of the legs, although lesions areoccasionally also found on anterior surfaces of thighs,the extensor surfaces of the forearms and rarely on theface and breast. The nodules are usually 5-20 mm indiameter, have ill defined margins and may becomeconfluent. They usually resolve over a week or two, thered color fading to purple and then brown, brownishpigment often persisting for several weeks. Recurrentcrops of lesions may occur. Fever may precede theeruptions by days or weeks and usually resolve withclearing of the lesion. Arthralgia is common in adultsaffecting the larger joints; wrists, elbows, knees or anklesand joints may some time be hot, swollen and tendermimicking acute rheumatic fever. The tuberculin test isalways strongly positive, in fact negative tuberculin testsuggests a non-tuberculous cause such as sarcoidosis.Histopathologically erythema nodosum is a commonvariety of panniculitis (non- suppurative inflammationof subcutaneous fat), which is a septal panniculitiswithout vasculitis.5,6 Another very similar entity iserythema induratum, a form of lobular panniculitis,which is often labelled ‘nodular vasculitis’ of unknownetiology.

The present case meticulously fits in to the foregoingclassical description of erhythema nodosum oftuberculous etiology. Over and above there were twoadditional remarkable findings in this case namelyi)Subungual erythematous spots of fingernails andii)phlyctenular conjuctivitis of both eyes. Subungualerythema observed in the fingernails in a case oftuberculosis with or without erythema nodosum has notbeen documented earlier and is a unique finding in thepresent case. We do not know exact etiopathogensis ofthis unique manifestation. However, the temporalrelationship between its onset alongwith other knowntuberculo-protein hypersensitivity phenomena andmanner of its resolutions similar to that of erythemanodosum after tuberculosis chemotherapy suggests thatnail involvement may also be an expression of hypersensitivity phenomenon akin to erythema nodosum.However no biopsy specimen from subungualerthymatous lesion could be taken to confirm thishypothesis.

The subungual erythema has also been described invarious conditions as half-an-half nail phenomenonoccurring mainly in those with chronic renal failure butalso in healthy persons. 7 Subungual erythema may alsocorrespond to recent subungual hemorrhage after traumaor patient receiving anti coagulant therapy. Subungual hemorrhage has also been observed in variety of systemicdiseases e.g. enterococcal endocarditis, staphylococcalendocarditis etc. Drug induced color changes in the nailshave been observed in patients receiving drugs such asclofazimine and a few cancer chemotherapeutic agents.The latter may be drug induced photo onycholysis aswell. However, our patient had not received any drugbefore presenting to us. Moreover, clinical presentationand rapid resolution after tuberculosis chemotherapyin present case do not favor these alternatives. Thus, byexclusion we presume that subungual erythematousdiscoloration in the present case was due to delayedhypersensitivity immune response encountered intuberculosis patients.

The second additional finding in the present case wasencountered in the form phlyctenular conjuctivitis inboth eyes. The phlyctenular conjuctivitis is a well-knownphenomenon, which reflects hypersensitivity totuberculo-proteins, again commonly encountered inchildren. This phenomenon also subsides by treatingthe underlying tuberculosis disease with appropriateanti TB chemotherapy. The other causes of poly arthritissuch as rheumatoid arthritis, systemic lupuserythematosus (SLE), systemic sclerosis, Sjogren’ssyndrome, tuberculous infective arthritis, sarcoidosis etc. were excluded with the help of relevant clinical,microbiological, serological and radiologicalinvestigations.

Apart from a unique finding of subungual erythemaof fingernails, the conglomeration of severalhypersensitivity phenomena of in a single patient is alsoan interesting coincidence.


1.Handa R, Raman M, Verma KK, et al. Panniculitides- AClinicopathologic Study. J Assoc Physicians India2002;50:1008-12.

2.Thompson BC. Discussion on the fate of the tuberculousprimary complex. Proc R Soc Med 1952;45:741.

3.Ustvedt HJ. Sex ratio in erythema nodosum. Osto City Hosp1977;27:9.

4. Wemambu SNC, Turk JL, Water MFR, Rees RJW. Erythemanodosum leprosum; a clinical manifestation of the arthusphenomenon. Lancet 1969;ii:933.

5.Barnhill RL, Busam KG. Vascular Diseases. In Elder D (ed.)Lever’s Histopathology of the Skin,8th edn. Philadelphia :Lippincott-Raven, 1997:191-2.

6.Callen JP, Zax RH. Panniculitis. In Maddison PJ (ed.) OxfordTextbook of Rheumatology, 2nd edn. Oxford: OxfordUniversity Press, 1998:1450-6.

.Lubach D, Strubbe I. The incidence of subungual erythema.Z Hautkr 1982;57:1487-95.